feat(transcription): add shared voice input support (#4232)

* feat(webui): add voice transcription input

* feat(webui): render ANSI output in code blocks

* refactor(webui): isolate voice recorder logic

* refactor(transcription): keep websocket ingress thin

* refactor(transcription): resolve channel audio settings on demand

* style(webui): neutralize voice waveform color

* feat(webui): add voice input tooltip

* feat(webui): add voice input keyboard shortcut

* fix(webui): distinguish voice shortcut platforms

* fix(webui): place voice button after model selector

* refactor(webui): share voice hold recording helpers

* fix(desktop): allow microphone voice input

* fix(webui): stabilize token usage month labels

* feat(webui): show voice input on settings overview

* fix(webui): label voice capability as recognition

* fix(webui): align capability overview status

* refactor(webui): isolate transcription socket handling

* fix(webui): soften silent voice waveform

* refactor(audio): clarify transcription service location

* docs(transcription): clarify audio and provider boundaries

* fix(exec): reduce session output polling flake

nanobot/utils/media_decode.py

@@ -18,13 +18,30 @@ from nanobot.utils.helpers import safe_filename
 DEFAULT_MAX_BYTES = 10 * 1024 * 1024
 MAX_FILE_SIZE = DEFAULT_MAX_BYTES
 
-_DATA_URL_RE = re.compile(r"^data:([^;]+);base64,(.+)$", re.DOTALL)
+_DATA_URL_RE = re.compile(r"^data:([^;,]+)(?:;[^,]*)*;base64,(.+)$", re.DOTALL)
+_MIME_EXTENSION_OVERRIDES = {
+    # Python's ``mimetypes`` maps browser-recorded audio/webm to ``.weba`` and
+    # audio/ogg to ``.oga`` on macOS. Some transcription APIs validate by the
+    # file extension and accept the canonical container extensions instead.
+    "application/ogg": ".ogg",
+    "audio/ogg": ".ogg",
+    "audio/mpga": ".mpga",
+    "audio/wav": ".wav",
+    "audio/webm": ".webm",
+    "audio/x-m4a": ".m4a",
+    "audio/x-wav": ".wav",
+    "audio/vnd.wave": ".wav",
+    "video/webm": ".webm",
+}
 
 
-class FileSizeExceeded(Exception):
+class FileSizeExceededError(Exception):
     """Raised when a decoded payload exceeds the caller's size limit."""
 
 
+FileSizeExceeded = FileSizeExceededError
+
+
 def save_base64_data_url(
     data_url: str,
     media_dir: Path,
@@ -40,7 +57,7 @@ def save_base64_data_url(
     m = _DATA_URL_RE.match(data_url)
     if not m:
         return None
-    mime_type, b64_payload = m.group(1), m.group(2)
+    mime_type, b64_payload = m.group(1).strip().lower(), m.group(2)
     try:
         raw = base64.b64decode(b64_payload)
     except Exception:
@@ -48,7 +65,7 @@ def save_base64_data_url(
     limit = DEFAULT_MAX_BYTES if max_bytes is None else max_bytes
     if len(raw) > limit:
         raise FileSizeExceeded(f"File exceeds {limit // (1024 * 1024)}MB limit")
-    ext = mimetypes.guess_extension(mime_type) or ".bin"
+    ext = _MIME_EXTENSION_OVERRIDES.get(mime_type) or mimetypes.guess_extension(mime_type) or ".bin"
     filename = f"{uuid.uuid4().hex[:12]}{ext}"
     dest = media_dir / safe_filename(filename)
     dest.write_bytes(raw)