feat(tools): expand command TTS output_format allowlist (m4a/aac/amr/opus)

Command-type TTS providers validated output_format against a hardcoded
{mp3,wav,ogg,flac} set; any other value was silently coerced back to mp3,
which then mismatched the output path the post-run check expects. This
blocked common ffmpeg-producible containers/codecs — notably m4a (AAC),
the portable choice for WeChat/iOS/mobile voice files — with no
config-only path (only a local source patch, lost on every update).

Widen COMMAND_TTS_OUTPUT_FORMATS to add m4a, aac, amr, opus. This only
permits a command provider to declare these; the user's command still
produces the file (e.g. via ffmpeg). No built-in provider behavior
changes and no new required config.

Update the two tests that pinned the old set, and add a positive case
covering the new formats. Document the supported output_format values.

tests/tools/test_tts_command_providers.py

@@ -243,10 +243,19 @@ class TestConfigGetters:
         assert _get_command_tts_output_format({"format": "ogg"}, "/tmp/clip.xyz") == "ogg"
 
     def test_output_format_rejects_unknown(self):
-        assert _get_command_tts_output_format({"format": "m4a"}) == DEFAULT_COMMAND_TTS_OUTPUT_FORMAT
+        assert _get_command_tts_output_format({"format": "midi"}) == DEFAULT_COMMAND_TTS_OUTPUT_FORMAT
 
     def test_output_format_supported_set(self):
-        assert COMMAND_TTS_OUTPUT_FORMATS == frozenset({"mp3", "wav", "ogg", "flac"})
+        assert COMMAND_TTS_OUTPUT_FORMATS == frozenset(
+            {"mp3", "wav", "ogg", "flac", "m4a", "aac", "amr", "opus"}
+        )
+
+    def test_output_format_accepts_extended_formats(self):
+        # m4a/aac/amr/opus are common ffmpeg-producible containers/codecs;
+        # honored both via explicit config and via the output path suffix.
+        for fmt in ("m4a", "aac", "amr", "opus"):
+            assert _get_command_tts_output_format({"format": fmt}) == fmt
+            assert _get_command_tts_output_format({}, f"/tmp/clip.{fmt}") == fmt
 
     def test_voice_compatible_boolean(self):
         assert _is_command_tts_voice_compatible({"voice_compatible": True}) is True

tools/tts_tool.py

@@ -623,7 +623,9 @@ BUILTIN_TTS_PROVIDERS = frozenset({
 
 DEFAULT_COMMAND_TTS_TIMEOUT_SECONDS = 120
 DEFAULT_COMMAND_TTS_OUTPUT_FORMAT = "mp3"
-COMMAND_TTS_OUTPUT_FORMATS = frozenset({"mp3", "wav", "ogg", "flac"})
+COMMAND_TTS_OUTPUT_FORMATS = frozenset(
+    {"mp3", "wav", "ogg", "flac", "m4a", "aac", "amr", "opus"}
+)
 DEFAULT_COMMAND_TTS_MAX_TEXT_LENGTH = 5000
 
 # Platforms whose native voice-bubble delivery requires Ogg/Opus audio.

website/docs/user-guide/features/tts.md

@@ -284,6 +284,8 @@ tts:
       output_format: wav
 ```
 
+**Supported `output_format` values:** `mp3` (default), `wav`, `ogg`, `flac`, `m4a`, `aac`, `amr`, `opus`. Your command must actually produce that format (e.g. via `ffmpeg`); Hermes only validates the declared value and names the output file accordingly. An unknown value falls back to `mp3`. The chosen format is also exposed to the command as the `{format}` placeholder.
+
 #### Example: Doubao (Chinese seed-tts-2.0)
 
 For high-quality Chinese TTS via ByteDance's [seed-tts-2.0](https://www.volcengine.com/docs/6561/1257544) bidirectional-streaming API, install the [`doubao-speech`](https://pypi.org/project/doubao-speech/) PyPI package and wire it in as a command provider: