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diff --git a/src/common-util/sugar.js b/src/common-util/sugar.js
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+// Syntactic sugar! (Mostly.)
+// Generic functions - these are useful just a8out everywhere.
+//
+// Friendly(!) disclaimer: these utility functions haven't 8een tested all that
+// much. Do not assume it will do exactly what you want it to do in all cases.
+// It will likely only do exactly what I want it to, and only in the cases I
+// decided were relevant enough to 8other handling.
+
+// Apparently JavaScript doesn't come with a function to split an array into
+// chunks! Weird. Anyway, this is an awesome place to use a generator, even
+// though we don't really make use of the 8enefits of generators any time we
+// actually use this. 8ut it's still awesome, 8ecause I say so.
+export function* splitArray(array, fn) {
+  let lastIndex = 0;
+  while (lastIndex < array.length) {
+    let nextIndex = array.findIndex((item, index) => index >= lastIndex && fn(item));
+    if (nextIndex === -1) {
+      nextIndex = array.length;
+    }
+    yield array.slice(lastIndex, nextIndex);
+    // Plus one because we don't want to include the dividing line in the
+    // next array we yield.
+    lastIndex = nextIndex + 1;
+  }
+}
+
+// Null-accepting function to check if an array or set is empty. Accepts null
+// (which is treated as empty) as a shorthand for "hey, check if this property
+// is an array with/without stuff in it" for objects where properties that are
+// PRESENT but don't currently have a VALUE are null (rather than undefined).
+export function empty(value) {
+  if (value === null) {
+    return true;
+  }
+
+  if (Array.isArray(value)) {
+    return value.length === 0;
+  }
+
+  if (value instanceof Set) {
+    return value.size === 0;
+  }
+
+  throw new Error(`Expected array, set, or null`);
+}
+
+// Repeats all the items of an array a number of times.
+export function repeat(times, array) {
+  if (times === 0) return [];
+  if (array === null || array === undefined) return [];
+  if (Array.isArray(array) && empty(array)) return [];
+
+  const out = [];
+
+  for (let n = 1; n <= times; n++) {
+    const value =
+      (typeof array === 'function'
+        ? array()
+        : array);
+
+    if (Array.isArray(value)) out.push(...value);
+    else out.push(value);
+  }
+
+  return out;
+}
+
+// Gets a random item from an array.
+export function pick(array) {
+  return array[Math.floor(Math.random() * array.length)];
+}
+
+// Gets the item at an index relative to another index.
+export function atOffset(array, index, offset, {
+  wrap = false,
+  valuePastEdge = null,
+} = {}) {
+  if (index === -1) {
+    return valuePastEdge;
+  }
+
+  if (offset === 0) {
+    return array[index];
+  }
+
+  if (wrap) {
+    return array[(index + offset) % array.length];
+  }
+
+  if (offset > 0 && index + offset > array.length - 1) {
+    return valuePastEdge;
+  }
+
+  if (offset < 0 && index + offset < 0) {
+    return valuePastEdge;
+  }
+
+  return array[index + offset];
+}
+
+// Gets the index of the first item that satisfies the provided function,
+// or, if none does, returns the length of the array (the index just past the
+// final item).
+export function findIndexOrEnd(array, fn) {
+  const index = array.findIndex(fn);
+  if (index >= 0) {
+    return index;
+  } else {
+    return array.length;
+  }
+}
+
+// Sums the values in an array, optionally taking a function which maps each
+// item to a number (handy for accessing a certain property on an array of like
+// objects). This also coalesces null values to zero, so if the mapping function
+// returns null (or values in the array are nullish), they'll just be skipped in
+// the sum.
+export function accumulateSum(array, fn = x => x) {
+  return array.reduce(
+    (accumulator, value, index, array) =>
+      accumulator +
+        fn(value, index, array) ?? 0,
+    0);
+}
+
+// Stitches together the items of separate arrays into one array of objects
+// whose keys are the corresponding items from each array at that index.
+// This is mostly useful for iterating over multiple arrays at once!
+export function stitchArrays(keyToArray) {
+  const errors = [];
+
+  for (const [key, value] of Object.entries(keyToArray)) {
+    if (value === null) continue;
+    if (Array.isArray(value)) continue;
+    errors.push(new TypeError(`(${key}) Expected array or null, got ${typeAppearance(value)}`));
+  }
+
+  if (!empty(errors)) {
+    throw new AggregateError(errors, `Expected arrays or null`);
+  }
+
+  const keys = Object.keys(keyToArray);
+  const arrays = Object.values(keyToArray).filter(val => Array.isArray(val));
+  const length = Math.max(...arrays.map(({length}) => length));
+  const results = [];
+
+  for (let i = 0; i < length; i++) {
+    const object = {};
+    for (const key of keys) {
+      object[key] =
+        (Array.isArray(keyToArray[key])
+          ? keyToArray[key][i]
+          : null);
+    }
+    results.push(object);
+  }
+
+  return results;
+}
+
+// Like Map.groupBy! Collects the items of an unsorted array into buckets
+// according to a per-item computed value.
+export function groupArray(items, fn) {
+  const buckets = new Map();
+
+  for (const [index, item] of Array.prototype.entries.call(items)) {
+    const key = fn(item, index);
+    if (buckets.has(key)) {
+      buckets.get(key).push(item);
+    } else {
+      buckets.set(key, [item]);
+    }
+  }
+
+  return buckets;
+}
+
+// Turns this:
+//
+//   [
+//     [123, 'orange', null],
+//     [456, 'apple', true],
+//     [789, 'banana', false],
+//     [1000, 'pear', undefined],
+//   ]
+//
+// Into this:
+//
+//   [
+//     [123, 456, 789, 1000],
+//     ['orange', 'apple', 'banana', 'pear'],
+//     [null, true, false, undefined],
+//   ]
+//
+// And back again, if you call it again on its results.
+export function transposeArrays(arrays) {
+  if (empty(arrays)) {
+    return [];
+  }
+
+  const length = arrays[0].length;
+  const results = new Array(length).fill(null).map(() => []);
+
+  for (const array of arrays) {
+    for (let i = 0; i < length; i++) {
+      results[i].push(array[i]);
+    }
+  }
+
+  return results;
+}
+
+export const mapInPlace = (array, fn) =>
+  array.splice(0, array.length, ...array.map(fn));
+
+export const unique = (arr) => Array.from(new Set(arr));
+
+export const compareArrays = (arr1, arr2, {checkOrder = true} = {}) =>
+  arr1.length === arr2.length &&
+  (checkOrder
+    ? arr1.every((x, i) => arr2[i] === x)
+    : arr1.every((x) => arr2.includes(x)));
+
+export function compareObjects(obj1, obj2, {
+  checkOrder = false,
+  checkSymbols = true,
+} = {}) {
+  const keys1 = Object.keys(obj1);
+  const keys2 = Object.keys(obj2);
+  if (!compareArrays(keys1, keys2, {checkOrder})) return false;
+
+  let syms1, syms2;
+  if (checkSymbols) {
+    syms1 = Object.getOwnPropertySymbols(obj1);
+    syms2 = Object.getOwnPropertySymbols(obj2);
+    if (!compareArrays(syms1, syms2, {checkOrder})) return false;
+  }
+
+  for (const key of keys1) {
+    if (obj2[key] !== obj1[key]) return false;
+  }
+
+  if (checkSymbols) {
+    for (const sym of syms1) {
+      if (obj2[sym] !== obj1[sym]) return false;
+    }
+  }
+
+  return true;
+}
+
+// Stolen from jq! Which pro8a8ly stole the concept from other places. Nice.
+export const withEntries = (obj, fn) => {
+  const result = fn(Object.entries(obj));
+  if (result instanceof Promise) {
+    return result.then(entries => Object.fromEntries(entries));
+  } else {
+    return Object.fromEntries(result);
+  }
+}
+
+export function setIntersection(set1, set2) {
+  const intersection = new Set();
+  for (const item of set1) {
+    if (set2.has(item)) {
+      intersection.add(item);
+    }
+  }
+  return intersection;
+}
+
+export function filterProperties(object, properties, {
+  preserveOriginalOrder = false,
+} = {}) {
+  if (typeof object !== 'object' || object === null) {
+    throw new TypeError(`Expected object to be an object, got ${typeAppearance(object)}`);
+  }
+
+  if (!Array.isArray(properties)) {
+    throw new TypeError(`Expected properties to be an array, got ${typeAppearance(properties)}`);
+  }
+
+  const filteredObject = {};
+
+  if (preserveOriginalOrder) {
+    for (const property of Object.keys(object)) {
+      if (properties.includes(property)) {
+        filteredObject[property] = object[property];
+      }
+    }
+  } else {
+    for (const property of properties) {
+      if (Object.hasOwn(object, property)) {
+        filteredObject[property] = object[property];
+      }
+    }
+  }
+
+  return filteredObject;
+}
+
+export function queue(array, max = 50) {
+  if (max === 0) {
+    return array.map((fn) => fn());
+  }
+
+  const begin = [];
+  let current = 0;
+  const ret = array.map(
+    (fn) =>
+      new Promise((resolve, reject) => {
+        begin.push(() => {
+          current++;
+          Promise.resolve(fn()).then((value) => {
+            current--;
+            if (current < max && begin.length) {
+              begin.shift()();
+            }
+            resolve(value);
+          }, reject);
+        });
+      })
+  );
+
+  for (let i = 0; i < max && begin.length; i++) {
+    begin.shift()();
+  }
+
+  return ret;
+}
+
+export function delay(ms) {
+  return new Promise((res) => setTimeout(res, ms));
+}
+
+export function promiseWithResolvers() {
+  let obj = {};
+
+  obj.promise =
+    new Promise((...opts) =>
+      ([obj.resolve, obj.reject] = opts));
+
+  return obj;
+}
+
+// Stolen from here: https://stackoverflow.com/a/3561711
+//
+// There's a proposal for a native JS function like this, 8ut it's not even
+// past stage ~~1~~ 2 yet: https://github.com/tc39/proposal-regex-escaping
+export function escapeRegex(string) {
+  return string.replace(/[-/\\^$*+?.()|[\]{}]/g, '\\$&');
+}
+
+export function splitKeys(key) {
+  return key.split(/(?<=(?<!\\)(?:\\\\)*)\./);
+}
+
+// Follows a key path like 'foo.bar.baz' to get an item nested deeply inside
+// an object.
+export function getNestedProp(obj, key) {
+  const recursive = (o, k) =>
+    (k.length === 1
+      ? o[k[0]]
+      : recursive(o[k[0]], k.slice(1)));
+
+  return recursive(obj, splitKeys(key));
+}
+
+// Gets the "look" of some arbitrary value. It's like typeof, but smarter.
+// Don't use this for actually validating types - it's only suitable for
+// inclusion in error messages.
+export function typeAppearance(value) {
+  if (value === null) return 'null';
+  if (value === undefined) return 'undefined';
+  if (Array.isArray(value)) return 'array';
+  return typeof value;
+}
+
+// Limits a string to the desired length, filling in an ellipsis at the end
+// if it cuts any text off.
+export function cut(text, length = 40) {
+  if (text.length >= length) {
+    const index = Math.max(1, length - 3);
+    return text.slice(0, index) + '...';
+  } else {
+    return text;
+  }
+}
+
+// Limits a string to the desired length, filling in an ellipsis at the start
+// if it cuts any text off.
+export function cutStart(text, length = 40) {
+  if (text.length >= length) {
+    const index = Math.min(text.length - 1, text.length - length + 3);
+    return '...' + text.slice(index);
+  } else {
+    return text;
+  }
+}
+
+// Wrapper function around wrap(), ha, ha - this requires the Node module
+// 'node-wrap'.
+export function indentWrap(str, {
+  wrap,
+  spaces = 0,
+  width = 60,
+  bullet = false,
+}) {
+  const wrapped =
+    wrap(str, {
+      width: width - spaces,
+      indent: ' '.repeat(spaces),
+    });
+
+  if (bullet) {
+    return wrapped.trimStart();
+  } else {
+    return wrapped;
+  }
+}
+
+// Annotates {index, length} results from another iterator with contextual
+// details, including:
+//
+// * its line and column numbers;
+// * if `formatWhere` is true (the default), a pretty-formatted,
+//   human-readable indication of the match's placement in the string;
+// * if `getContainingLine` is true, the entire line (or multiple lines)
+//   of text containing the match.
+//
+export function* iterateMultiline(content, iterator, {
+  formatWhere = true,
+  getContainingLine = false,
+} = {}) {
+  const lineRegexp = /\n/g;
+  const isMultiline = content.includes('\n');
+
+  let lineNumber = 0;
+  let startOfLine = 0;
+  let previousIndex = 0;
+
+  const countLineBreaks = (index, length) => {
+    const range = content.slice(index, index + length);
+    const lineBreaks = Array.from(range.matchAll(lineRegexp));
+    if (!empty(lineBreaks)) {
+      lineNumber += lineBreaks.length;
+      startOfLine = index + lineBreaks.at(-1).index + 1;
+    }
+  };
+
+  for (const result of iterator) {
+    const {index, length} = result;
+
+    countLineBreaks(previousIndex, index - previousIndex);
+
+    const matchStartOfLine = startOfLine;
+
+    previousIndex = index + length;
+
+    const columnNumber = index - startOfLine;
+
+    const where =
+      (formatWhere && isMultiline
+        ? `line: ${lineNumber + 1}, col: ${columnNumber + 1}`
+     : formatWhere
+        ? `pos: ${index + 1}`
+        : null);
+
+    countLineBreaks(index, length);
+
+    let containingLine = null;
+    if (getContainingLine) {
+      const nextLineResult =
+        content
+          .slice(previousIndex)
+          .matchAll(lineRegexp)
+          .next();
+
+      const nextStartOfLine =
+        (nextLineResult.done
+          ? content.length
+          : previousIndex + nextLineResult.value.index);
+
+      containingLine =
+        content.slice(matchStartOfLine, nextStartOfLine);
+    }
+
+    yield {
+      ...result,
+      lineNumber,
+      columnNumber,
+      where,
+      containingLine,
+    };
+  }
+}
+
+// Iterates over regular expression matches within a single- or multiline
+// string, yielding each match as well as contextual details; this accepts
+// the same options (and provides the same context) as iterateMultiline.
+export function* matchMultiline(content, matchRegexp, options) {
+  const matchAllIterator =
+    content.matchAll(matchRegexp);
+
+  const cleanMatchAllIterator =
+    (function*() {
+      for (const match of matchAllIterator) {
+        yield {
+          index: match.index,
+          length: match[0].length,
+          match,
+        };
+      }
+    })();
+
+  const multilineIterator =
+    iterateMultiline(content, cleanMatchAllIterator, options);
+
+  yield* multilineIterator;
+}
+
+// Binds default values for arguments in a {key: value} type function argument
+// (typically the second argument, but may be overridden by providing a
+// [bindOpts.bindIndex] argument). Typically useful for preparing a function for
+// reuse within one or multiple other contexts, which may not be aware of
+// required or relevant values provided in the initial context.
+//
+// This function also passes the identity of `this` through (the returned value
+// is not an arrow function), though note it's not a true bound function either
+// (since Function.prototype.bind only supports positional arguments, not
+// "options" specified via key/value).
+//
+export function bindOpts(fn, bind) {
+  const bindIndex = bind[bindOpts.bindIndex] ?? 1;
+
+  const bound = function (...args) {
+    const opts = args[bindIndex] ?? {};
+    return Reflect.apply(fn, this, [
+      ...args.slice(0, bindIndex),
+      {...bind, ...opts}
+    ]);
+  };
+
+  annotateFunction(bound, {
+    name: fn,
+    trait: 'options-bound',
+  });
+
+  for (const [key, descriptor] of Object.entries(Object.getOwnPropertyDescriptors(fn))) {
+    if (key === 'length') continue;
+    if (key === 'name') continue;
+    if (key === 'arguments') continue;
+    if (key === 'caller') continue;
+    if (key === 'prototype') continue;
+    Object.defineProperty(bound, key, descriptor);
+  }
+
+  return bound;
+}
+
+bindOpts.bindIndex = Symbol();
+
+// Sorts multiple arrays by an arbitrary function (which is the last argument).
+// Paired values from each array are provided to the callback sequentially:
+//
+//   (a_fromFirstArray, b_fromFirstArray,
+//    a_fromSecondArray, b_fromSecondArray,
+//    a_fromThirdArray, b_fromThirdArray) =>
+//     relative positioning (negative, positive, or zero)
+//
+// Like native single-array sort, this is a mutating function.
+export function sortMultipleArrays(...args) {
+  const arrays = args.slice(0, -1);
+  const fn = args.at(-1);
+
+  const length = arrays[0].length;
+  const symbols = new Array(length).fill(null).map(() => Symbol());
+  const indexes = Object.fromEntries(symbols.map((symbol, index) => [symbol, index]));
+
+  symbols.sort((a, b) => {
+    const indexA = indexes[a];
+    const indexB = indexes[b];
+
+    const args = [];
+    for (let i = 0; i < arrays.length; i++) {
+      args.push(arrays[i][indexA]);
+      args.push(arrays[i][indexB]);
+    }
+
+    return fn(...args);
+  });
+
+  for (const array of arrays) {
+    // Note: We're mutating this array pulling values from itself, but only all
+    // at once after all those values have been pulled.
+    array.splice(0, array.length, ...symbols.map(symbol => array[indexes[symbol]]));
+  }
+
+  return arrays;
+}
+
+// Filters multiple arrays by an arbitrary function (which is the last argument).
+// Values from each array are provided to the callback sequentially:
+//
+//   (value_fromFirstArray,
+//    value_fromSecondArray,
+//    value_fromThirdArray,
+//    index,
+//    [firstArray, secondArray, thirdArray]) =>
+//      true or false
+//
+// Please be aware that this is a mutating function, unlike native single-array
+// filter. The mutated arrays are returned. Also attached under `.removed` are
+// corresponding arrays of items filtered out.
+export function filterMultipleArrays(...args) {
+  const arrays = args.slice(0, -1);
+  const fn = args.at(-1);
+
+  const removed = new Array(arrays.length).fill(null).map(() => []);
+
+  for (let i = arrays[0].length - 1; i >= 0; i--) {
+    const args = arrays.map(array => array[i]);
+    args.push(i, arrays);
+
+    if (!fn(...args)) {
+      for (let j = 0; j < arrays.length; j++) {
+        const item = arrays[j][i];
+        arrays[j].splice(i, 1);
+        removed[j].unshift(item);
+      }
+    }
+  }
+
+  Object.assign(arrays, {removed});
+  return arrays;
+}
+
+// Corresponding filter function for sortByCount. By default, items whose
+// corresponding count is zero will be removed.
+export function filterByCount(data, counts, {
+  min = 1,
+  max = Infinity,
+} = {}) {
+  filterMultipleArrays(data, counts, (data, count) =>
+    count >= min && count <= max);
+}
+
+// Reduces multiple arrays with an arbitrary function (which is the last
+// argument). Note that this reduces into multiple accumulators, one for
+// each input array, not just a single value. That's reflected in both the
+// callback parameters:
+//
+//   (accumulator1,
+//    accumulator2,
+//    value_fromFirstArray,
+//    value_fromSecondArray,
+//    index,
+//    [firstArray, secondArray]) =>
+//      [newAccumulator1, newAccumulator2]
+//
+// As well as the final return value of reduceMultipleArrays:
+//
+//   [finalAccumulator1, finalAccumulator2]
+//
+// This is not a mutating function.
+export function reduceMultipleArrays(...args) {
+  const [arrays, fn, initialAccumulators] =
+    (typeof args.at(-1) === 'function'
+      ? [args.slice(0, -1), args.at(-1), null]
+      : [args.slice(0, -2), args.at(-2), args.at(-1)]);
+
+  if (empty(arrays[0])) {
+    throw new TypeError(`Reduce of empty arrays with no initial value`);
+  }
+
+  let [accumulators, i] =
+    (initialAccumulators
+      ? [initialAccumulators, 0]
+      : [arrays.map(array => array[0]), 1]);
+
+  for (; i < arrays[0].length; i++) {
+    const args = [...accumulators, ...arrays.map(array => array[i])];
+    args.push(i, arrays);
+    accumulators = fn(...args);
+  }
+
+  return accumulators;
+}
+
+export function chunkByConditions(array, conditions) {
+  if (empty(array)) {
+    return [];
+  }
+
+  if (empty(conditions)) {
+    return [array];
+  }
+
+  const out = [];
+  let cur = [array[0]];
+  for (let i = 1; i < array.length; i++) {
+    const item = array[i];
+    const prev = array[i - 1];
+    let chunk = false;
+    for (const condition of conditions) {
+      if (condition(item, prev)) {
+        chunk = true;
+        break;
+      }
+    }
+    if (chunk) {
+      out.push(cur);
+      cur = [item];
+    } else {
+      cur.push(item);
+    }
+  }
+  out.push(cur);
+  return out;
+}
+
+export function chunkByProperties(array, properties) {
+  return chunkByConditions(
+    array,
+    properties.map((p) => (a, b) => {
+      if (a[p] instanceof Date && b[p] instanceof Date) return +a[p] !== +b[p];
+
+      if (a[p] !== b[p]) return true;
+
+      // Not sure if this line is still necessary with the specific check for
+      // d8tes a8ove, 8ut, uh, keeping it anyway, just in case....?
+      if (a[p] != b[p]) return true;
+
+      return false;
+    })
+  ).map((chunk) => ({
+    ...Object.fromEntries(properties.map((p) => [p, chunk[0][p]])),
+    chunk,
+  }));
+}
+
+export function chunkMultipleArrays(...args) {
+  const arrays = args.slice(0, -1);
+  const fn = args.at(-1);
+
+  if (arrays[0].length === 0) {
+    return [];
+  }
+
+  const newChunk = index => arrays.map(array => [array[index]]);
+  const results = [newChunk(0)];
+
+  for (let i = 1; i < arrays[0].length; i++) {
+    const current = results.at(-1);
+
+    const args = [];
+    for (let j = 0; j < arrays.length; j++) {
+      const item = arrays[j][i];
+      const previous = current[j].at(-1);
+      args.push(item, previous);
+    }
+
+    if (fn(...args)) {
+      results.push(newChunk(i));
+      continue;
+    }
+
+    for (let j = 0; j < arrays.length; j++) {
+      current[j].push(arrays[j][i]);
+    }
+  }
+
+  return results;
+}
+
+// Delicious function annotations, such as:
+//
+//   (*bound) soWeAreBackInTheMine
+//   (data *unfulfilled) generateShrekTwo
+//
+export function annotateFunction(fn, {
+  name: nameOrFunction = null,
+  description: newDescription,
+  trait: newTrait,
+}) {
+  let name;
+
+  if (typeof nameOrFunction === 'function') {
+    name = nameOrFunction.name;
+  } else if (typeof nameOrFunction === 'string') {
+    name = nameOrFunction;
+  }
+
+  name ??= fn.name ?? 'anonymous';
+
+  const match = name.match(/^ *(?<prefix>.*?) *\((?<description>.*)( #(?<trait>.*))?\) *(?<suffix>.*) *$/);
+
+  let prefix, suffix, description, trait;
+  if (match) {
+    ({prefix, suffix, description, trait} = match.groups);
+  }
+
+  prefix ??= '';
+  suffix ??= name;
+  description ??= '';
+  trait ??= '';
+
+  if (newDescription) {
+    if (description) {
+      description += '; ' + newDescription;
+    } else {
+      description = newDescription;
+    }
+  }
+
+  if (newTrait) {
+    if (trait) {
+      trait += ' #' + newTrait;
+    } else {
+      trait = '#' + newTrait;
+    }
+  }
+
+  let parenthesesPart;
+
+  if (description && trait) {
+    parenthesesPart = `${description} ${trait}`;
+  } else if (description || trait) {
+    parenthesesPart = description || trait;
+  } else {
+    parenthesesPart = '';
+  }
+
+  let finalName;
+
+  if (prefix && parenthesesPart) {
+    finalName = `${prefix} (${parenthesesPart}) ${suffix}`;
+  } else if (parenthesesPart) {
+    finalName = `(${parenthesesPart}) ${suffix}`;
+  } else {
+    finalName = suffix;
+  }
+
+  Object.defineProperty(fn, 'name', {value: finalName});
+}