style: fix the lint errors the repaired ESLint run surfaced

With `pnpm run lint` working again, ESLint reports real findings for the
first time. These are mechanical, behaviour-preserving fixes:

- `mocha/no-synchronous-tests`: mark the reported `it`/`before` callbacks
  `async`. Mocha awaits the returned promise, so a passing synchronous
  body still passes.
- unused `require`s removed, over-long lines wrapped, and the small
  residue the rules left behind.

No test expectation, hook or runtime behaviour is changed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013S4pYSjwUsiZtdtMMpW7bw

Author: JohnMcLear

static/js/shared.js

@@ -15,7 +15,7 @@ const ALLOWED_COLORS = new Set([
   'black', 'red', 'green', 'blue', 'yellow', 'orange',
 ]);
 
-const NAMED_TO_PALETTE = (raw) => {
+const namedToPalette = (raw) => {
   const v = raw.toLowerCase().trim();
   if (ALLOWED_COLORS.has(v)) return v;
   // Word/LibreOffice often emit hex (e.g. #FF0000). Fold common values
@@ -35,7 +35,7 @@ exports.collectContentPre = (hookName, context) => {
   if (context.styl) {
     const m = STYLE_COLOR_RE.exec(context.styl);
     if (m) {
-      const color = NAMED_TO_PALETTE(m[1]);
+      const color = namedToPalette(m[1]);
       if (color) context.cc.doAttrib(context.state, `color::${color}`);
     }
   }

static/tests/backend/specs/api/exportHTML.js

@@ -14,7 +14,8 @@ const createPad = async (padID) => {
 };
 
 const setHTML = async (padID, html) => {
-  const res = await agent.get(`/api/${apiVersion}/setHTML?padID=${padID}&html=${encodeURIComponent(html)}`)
+  const res = await agent
+      .get(`/api/${apiVersion}/setHTML?padID=${padID}&html=${encodeURIComponent(html)}`)
       .set('Authorization', await common.generateJWTToken());
   if (res.body.code !== 0) throw new Error('Unable to set pad HTML');
   return padID;

static/tests/backend/specs/language_refresh.js

@@ -10,9 +10,9 @@ const indexPath = path.resolve(
 describe(__filename, function () {
   let src;
 
-  before(function () { src = fs.readFileSync(indexPath, 'utf8'); });
+  before(async function () { src = fs.readFileSync(indexPath, 'utf8'); });
 
-  it('postAceInit rebinds niceSelect on html10n language change (#21)', function () {
+  it('postAceInit rebinds niceSelect on html10n language change (#21)', async function () {
     // niceSelect renders a copy of the <select> at init time and does not
     // observe option-text mutations. After html10n rewrites the <select>
     // options for the new locale, the custom dropdown must be refreshed