Editor: Find & Replace, read-aloud, backup, typography, phonetic, org niceties

Writer power-ups (Phase 11), plus the selection-bubble vs copy/paste fix.

- Find & Replace (Ctrl/Cmd+F): SearchHighlight decoration extension +
  FindReplace bar (match-case, replace-all back-to-front, scroll without
  popping the selection bubble).
- Read-aloud (Web Speech, offline) on the word card and selection bubble.
- Keyboard/touch access to the ESL helpers: Ctrl/Cmd+D look up word at caret,
  Ctrl/Cmd+J rewrite selection, touch long-press lookup. Refactored the
  right-click handler into a shared openWordLookup(pos).
- Whole-corpus backup: GET /api/docs/export-all zips every doc (md/docx),
  de-dupes filenames, dated name; sidebar download links. TestExportAll.
- Smart typography input rules (curly quotes/em-dash/ellipsis), ASCII-only so
  CJK is untouched.
- Duplicate doc, sidebar sort (Recent/Title/Longest), toolbar outline popover.
- English phonetic (chosen over pinyin for an English learner): ECDICT-built
  phonetic.json.gz (46,579 words) + Result.Phonetic + WordCard IPA line;
  scripts/build_phonetic.py (full build + --seed fallback).
- Selection bubble no longer blocks copy/paste: deferred to pointer-up and made
  click-through except on its buttons.

Claude-Session: https://claude.ai/code/session_016Yr6jELuRc7hyzYLccQKZd

web/src/audio/speech.ts

@@ -0,0 +1,32 @@
+// Read-aloud via the browser's Web Speech API — an offline pronunciation aid for
+// an ESL writer: hear how an English word or passage sounds. No model, no
+// network, no extra weight in the binary. Feature-detected so the buttons that
+// use it can hide where speech isn't available.
+
+export function speechSupported(): boolean {
+  return typeof window !== 'undefined' && 'speechSynthesis' in window && 'SpeechSynthesisUtterance' in window
+}
+
+// pickVoice prefers an exact locale match (e.g. en-US), then any voice in the
+// same language family (en-*). Returns undefined to let the engine default.
+function pickVoice(lang: string): SpeechSynthesisVoice | undefined {
+  const voices = window.speechSynthesis.getVoices()
+  const base = lang.split('-')[0]
+  return voices.find((v) => v.lang === lang) || voices.find((v) => v.lang?.startsWith(base))
+}
+
+// speak reads `text` aloud, cancelling anything already in flight so rapid taps
+// don't queue up. `lang` defaults to US English (the language she's learning);
+// pass a zh locale to hear a Chinese passage. A touch slower than default so
+// learners can follow along.
+export function speak(text: string, lang = 'en-US'): void {
+  if (!speechSupported() || !text.trim()) return
+  const synth = window.speechSynthesis
+  synth.cancel()
+  const utterance = new SpeechSynthesisUtterance(text)
+  utterance.lang = lang
+  const voice = pickVoice(lang)
+  if (voice) utterance.voice = voice
+  utterance.rate = 0.95
+  synth.speak(utterance)
+}