fix(#2931): Edge TTS playback path (GET->POST), stoppable hands-free audio, test isolation

Both advisors (Opus MUST-FIX + Codex SHIP-ONLY-WITH-FIXES) caught that the Edge
TTS playback was broken despite the settings selector working:

1. ui.js _playEdgeTts used new Audio('/api/tts?text=...') — a GET — but /api/tts
   is POST-only (405) and registered only in handle_post. The per-message speaker
   button + auto-read silently failed in edge mode, and the GET leaked message
   text into the query string/access log. Rewritten to POST JSON + blob object
   URL (mirrors the working boot.js path), and now surfaces server errors
   (503 not-installed, 429 rate-limit) via toast instead of silent dead air.
2. boot.js hands-free Edge audio was a local var never assigned to the shared
   _playingEdgeAudio handle, so stopTTS() (from _deactivate) couldn't stop it.
   Now registered + cleared on end/error.
3. Test isolation: the _tts_limiter function-attribute singleton persisted across
   the whole suite, flaking 2 of my endpoint tests in the full run. Converted the
   reset to an autouse fixture (before+after each) + unique per-test client IPs.

static/boot.js

@@ -913,18 +913,26 @@ window._micPendingSend=window._micPendingSend||false;
       .then(blob => {
         const url = URL.createObjectURL(blob);
         const audio = new Audio(url);
+        // Register with the shared handle (declared in ui.js, same global scope;
+        // both scripts are fully evaluated before any voice interaction) so
+        // stopTTS() — called from _deactivate() — can actually pause hands-free
+        // Edge playback. Without this the audio is local here and unstoppable.
+        _playingEdgeAudio=audio;
         audio.onended = () => {
           _ttsSpeaking=false;
+          if(_playingEdgeAudio===audio) _playingEdgeAudio=null;
           URL.revokeObjectURL(url);
           if(_voiceModeActive) setTimeout(()=>_startListening(),500);
         };
         audio.onerror = () => {
           _ttsSpeaking=false;
+          if(_playingEdgeAudio===audio) _playingEdgeAudio=null;
           URL.revokeObjectURL(url);
           if(_voiceModeActive) setTimeout(()=>_startListening(),1000);
         };
         audio.play().catch(e => {
           _ttsSpeaking=false;
+          if(_playingEdgeAudio===audio) _playingEdgeAudio=null;
           if(_voiceModeActive) setTimeout(()=>_startListening(),1000);
         });
       })

static/ui.js

@@ -4421,29 +4421,44 @@ function _playEdgeTts(text, btn){
   const voice=localStorage.getItem('hermes-tts-voice')||'zh-CN-XiaoxiaoNeural';
   const savedRate=parseFloat(localStorage.getItem('hermes-tts-rate'));
   const savedPitch=parseFloat(localStorage.getItem('hermes-tts-pitch'));
-  let rateParam='', pitchParam='';
-  if(!isNaN(savedRate)){
-    const pct=Math.round((savedRate-1)*100);
-    const sign=pct>=0?'+':'';
-    rateParam='&rate='+encodeURIComponent(sign+pct+'%');
-  }
-  if(!isNaN(savedPitch)){
-    const hz=Math.round((savedPitch-1)*50);
-    const sign=hz>=0?'+':'';
-    pitchParam='&pitch='+encodeURIComponent(sign+hz+'Hz');
-  }
-  const url='/api/tts?text='+encodeURIComponent(text)+'&voice='+encodeURIComponent(voice)+rateParam+pitchParam;
+  let rate='', pitch='';
+  if(!isNaN(savedRate)){const pct=Math.round((savedRate-1)*100);const sign=pct>=0?'+':'';rate=sign+pct+'%';}
+  if(!isNaN(savedPitch)){const hz=Math.round((savedPitch-1)*50);const sign=hz>=0?'+':'';pitch=sign+hz+'Hz';}
   if(btn) btn.dataset.speaking='1';
   _ttsSpeaking=true;
-  const audio=new Audio(url);
-  _playingEdgeAudio=audio;
-  audio.onended=function(){_ttsSpeaking=false;_playingEdgeAudio=null;if(btn)btn.dataset.speaking='0';};
-  audio.onerror=function(){_ttsSpeaking=false;_playingEdgeAudio=null;if(btn)btn.dataset.speaking='0';};
-  audio.play().catch(function(e){
+  // /api/tts is POST-only (and behind the same-origin CSRF gate); GET via
+  // new Audio(url) would 405 and silently fail, and would also leak the message
+  // text into the query string / access log. POST the JSON body, then play the
+  // returned audio via an object URL — mirrors the working boot.js edge path.
+  const _fail=function(msg){
     _ttsSpeaking=false;_playingEdgeAudio=null;
     if(btn)btn.dataset.speaking='0';
-    showToast('Edge TTS error: '+e.message);
-  });
+    if(msg&&typeof showToast==='function') showToast(msg,4000,'error');
+  };
+  fetch(new URL('api/tts', document.baseURI || location.href).href, {
+    method:'POST',
+    headers:{'Content-Type':'application/json'},
+    body:JSON.stringify({text:text, voice:voice, rate:rate, pitch:pitch})
+  })
+  .then(function(r){
+    if(!r.ok){
+      // Surface the server error (e.g. 503 "edge-tts not installed", 429 rate limit)
+      return r.json().catch(function(){return {};}).then(function(j){
+        throw new Error((j&&j.error)||('TTS request failed: '+r.status));
+      });
+    }
+    return r.blob();
+  })
+  .then(function(blob){
+    const url=URL.createObjectURL(blob);
+    const audio=new Audio(url);
+    _playingEdgeAudio=audio;
+    const _cleanup=function(){_ttsSpeaking=false;_playingEdgeAudio=null;if(btn)btn.dataset.speaking='0';try{URL.revokeObjectURL(url);}catch(_){}};
+    audio.onended=_cleanup;
+    audio.onerror=function(){_cleanup();};
+    audio.play().catch(function(e){_cleanup();showToast('Edge TTS error: '+(e&&e.message||e));});
+  })
+  .catch(function(e){ _fail((e&&e.message)||'Edge TTS failed'); });
 }
 
 function stopTTS(){

tests/test_issue2931_edge_tts_endpoint.py

@@ -8,6 +8,8 @@ edge_tts import / Communicate call.
 import io
 import json
 
+import pytest
+
 import api.routes as routes
 
 
@@ -50,15 +52,23 @@ def _reset_limiter():
         del routes._handle_tts._tts_limiter
 
 
-def test_tts_requires_post():
+@pytest.fixture(autouse=True)
+def _fresh_tts_limiter():
+    # The limiter is a function-attribute singleton that persists across the
+    # whole test session; reset it before AND after every test in this module so
+    # neither prior suite state nor these tests leak rate-limit state.
     _reset_limiter()
+    yield
+    _reset_limiter()
+
+
+def test_tts_requires_post():
     h = _post({"text": "hello"}, command="GET")
     routes._handle_tts(h, None)
     assert h.status == 405
 
 
 def test_tts_requires_text():
-    _reset_limiter()
     h = _post({"text": "   "})
     routes._handle_tts(h, None)
     assert h.status == 400
@@ -66,32 +76,29 @@ def test_tts_requires_text():
 
 
 def test_tts_rejects_overlong_text():
-    _reset_limiter()
-    h = _post({"text": "x" * 5001})
+    h = _post({"text": "x" * 5001}, client="10.0.0.1")
     routes._handle_tts(h, None)
     assert h.status == 400
     assert "too long" in (h.payload() or {}).get("error", "")
 
 
 def test_tts_rejects_unknown_voice():
-    _reset_limiter()
-    h = _post({"text": "hello", "voice": "evil-voice-injection"}, client="5.6.7.8")
+    h = _post({"text": "hello", "voice": "evil-voice-injection"}, client="10.0.0.2")
     routes._handle_tts(h, None)
     assert h.status == 400
     assert "invalid voice" in (h.payload() or {}).get("error", "")
 
 
 def test_tts_rate_limits_second_immediate_request():
-    _reset_limiter()
     # The limiter runs (and records the client) BEFORE the voice allowlist and
     # before any edge-tts synthesis. Use an invalid voice so the first request
     # still registers with the limiter but returns at the allowlist (400) without
     # making a real network call; the second immediate request from the SAME
-    # client is then throttled (429).
-    h1 = _post({"text": "hello", "voice": "not-a-real-voice"}, client="9.9.9.9")
+    # client is then throttled (429). Unique client IP avoids any cross-test key
+    # collision (the autouse fixture also resets the limiter each test).
+    h1 = _post({"text": "hello", "voice": "not-a-real-voice"}, client="10.0.0.3")
     routes._handle_tts(h1, None)
     assert h1.status == 400  # rejected at allowlist, limiter recorded the client
-    h2 = _post({"text": "hello", "voice": "not-a-real-voice"}, client="9.9.9.9")
+    h2 = _post({"text": "hello", "voice": "not-a-real-voice"}, client="10.0.0.3")
     routes._handle_tts(h2, None)
     assert h2.status == 429
-    _reset_limiter()