feat: replace wanakana with english-to-kana 49K dictionary

- Vendor english-kana-matcher.js (english-to-kana, MIT, 49216 words)
- Rewrite bridge: dictionary lookup + letter-by-letter fallback for OOV words
- Convert English punctuation (,.!?) to Japanese pauses (、。)
- Fix Chinese fullwidth comma being stripped by filter_kana
- Preserve decimal points in numbers (3.5 -> スリーファイブ)
- main.py now applies filter_kana (matches web UI behavior)
- Remove wanakana dependency; rebuild portable zip (82.5 MB)

build.py

@@ -135,13 +135,15 @@ def main() -> int:
     safe_copy_tree(aq_src / "node_modules", aq_dst / "node_modules",
                    ignore_patterns=("bililive-touhou-tts",))
 
-    # ── 4. kuroshiro node_modules ──────────────────────────────────────
-    step("Copying kuroshiro node_modules")
-    safe_copy_tree(ROOT / "node_modules", BUILD_DIR / "node_modules")
+    # ── 4. node_modules (if any) ───────────────────────────────────────
+    if (ROOT / "node_modules").exists():
+        step("Copying node_modules")
+        safe_copy_tree(ROOT / "node_modules", BUILD_DIR / "node_modules")
 
     # ── 5. Bridge + config ─────────────────────────────────────────────
     step("Copying bridge files")
     shutil.copy2(ROOT / "tts_bridge.js", BUILD_DIR / "tts_bridge.js")
+    shutil.copy2(ROOT / "english-kana-matcher.js", BUILD_DIR / "english-kana-matcher.js")
     shutil.copy2(ROOT / "package.json", BUILD_DIR / "package.json")
     print("  OK")