feat(tts): add French (fr-CA, fr-FR) voices to Edge TTS allowlist

Adds 4 fr-CA + 3 fr-FR Edge neural voices so francophone users can use
the Edge TTS engine instead of receiving HTTP 400 "invalid voice" on
every utterance. Pure superset of the existing allowlist; no validation
or rate-limit behavior changes.

Tests mirror the test_issue2931 in-process / mocked-edge_tts pattern:
each new voice is parametrized through _handle_tts and asserted to
reach synthesis (HTTP 200); fr-BE-CharlineNeural (real Edge voice
but intentionally unlisted) is asserted to still 400.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

api/routes.py

@@ -10318,7 +10318,10 @@ def _handle_tts(handler, parsed):
     allowed = {
         "zh-CN-XiaoxiaoNeural", "zh-CN-XiaoyiNeural", "zh-CN-YunxiNeural",
         "zh-CN-YunjianNeural", "zh-CN-YunyangNeural",
-        "en-US-AriaNeural", "en-US-GuyNeural"
+        "en-US-AriaNeural", "en-US-GuyNeural",
+        "fr-CA-AntoineNeural", "fr-CA-JeanNeural",
+        "fr-CA-SylvieNeural", "fr-CA-ThierryNeural",
+        "fr-FR-DeniseNeural", "fr-FR-EloiseNeural", "fr-FR-HenriNeural",
     }
     if voice not in allowed:
         from api.helpers import bad as _bad

tests/test_french_voices_tts_allowlist.py

@@ -0,0 +1,108 @@
+"""Coverage for French voices in the Edge TTS allowlist.
+
+Mirrors the in-process / mocked-edge_tts pattern from
+test_issue2931_edge_tts_endpoint.py to assert each French voice in the
+allowlist reaches synthesis (HTTP 200) and that an unlisted French locale
+(fr-BE) is still rejected at the allowlist (HTTP 400).
+"""
+import io
+import json
+import sys
+from types import SimpleNamespace
+
+import pytest
+
+import api.routes as routes
+
+
+class _FakeHandler:
+    def __init__(self, body: bytes, command: str = "POST", headers=None, client="1.2.3.4"):
+        self.command = command
+        self.rfile = io.BytesIO(body)
+        self.wfile = io.BytesIO()
+        self.headers = headers or {}
+        self.headers.setdefault("Content-Length", str(len(body)))
+        self.client_address = (client, 12345)
+        self.status = None
+        self.sent_headers = {}
+
+    def send_response(self, status):
+        self.status = status
+
+    def send_header(self, key, value):
+        self.sent_headers[key] = value
+
+    def end_headers(self):
+        pass
+
+    def payload(self):
+        try:
+            return json.loads(self.wfile.getvalue().decode("utf-8"))
+        except Exception:
+            return None
+
+
+def _post(body_dict, **kw):
+    body = json.dumps(body_dict).encode()
+    return _FakeHandler(body, **kw)
+
+
+def _reset_limiter():
+    if hasattr(routes._handle_tts, "_tts_limiter"):
+        del routes._handle_tts._tts_limiter
+
+
+@pytest.fixture(autouse=True)
+def _fresh_tts_limiter(monkeypatch):
+    import api.auth as _auth
+    monkeypatch.setattr(_auth, "is_auth_enabled", lambda: False)
+    monkeypatch.setattr(routes, "is_auth_enabled", lambda: False, raising=False)
+    monkeypatch.delenv("HERMES_WEBUI_TRUST_FORWARDED_FOR", raising=False)
+    _reset_limiter()
+    yield
+    _reset_limiter()
+
+
+FRENCH_VOICES = [
+    "fr-CA-AntoineNeural",
+    "fr-CA-JeanNeural",
+    "fr-CA-SylvieNeural",
+    "fr-CA-ThierryNeural",
+    "fr-FR-DeniseNeural",
+    "fr-FR-EloiseNeural",
+    "fr-FR-HenriNeural",
+]
+
+
+@pytest.mark.parametrize("voice", FRENCH_VOICES)
+def test_french_voice_in_allowlist_reaches_synthesis(monkeypatch, voice):
+    captured = {}
+
+    class FakeCommunicate:
+        def __init__(self, text, voice, **kwargs):
+            captured["text"] = text
+            captured["voice"] = voice
+
+        def stream_sync(self):
+            yield {"type": "audio", "data": b"abc"}
+
+    monkeypatch.setitem(sys.modules, "edge_tts", SimpleNamespace(Communicate=FakeCommunicate))
+
+    # Unique client per voice so the 2s per-client rate limiter does not throttle
+    # successive parametrized runs in this module.
+    client = f"10.99.0.{FRENCH_VOICES.index(voice) + 1}"
+    h = _post({"text": "Bonjour", "voice": voice}, client=client)
+    routes._handle_tts(h, None)
+
+    assert h.status == 200, h.payload()
+    assert captured["voice"] == voice
+
+
+def test_unlisted_french_locale_still_rejected():
+    # fr-BE is a real Edge voice locale but is intentionally not in the
+    # allowlist; it must still be rejected at the voice check before any
+    # synthesis is attempted.
+    h = _post({"text": "Bonjour", "voice": "fr-BE-CharlineNeural"}, client="10.99.1.1")
+    routes._handle_tts(h, None)
+    assert h.status == 400
+    assert "invalid voice" in (h.payload() or {}).get("error", "")