Add rendering and support for a karaoke-style text-to-speechprogress bar in assistant messages so users can see the currently
spoken sentence and highlighted word during playback.
- Append TTS karaoke bar to AssistantMessageWidget when the message is
the active TTS target and playback is speaking/paused/loading.
- Implement _buildKaraokeBar to render the active sentence with a
highlighted word span, using ConduitCard and theme styles.
- Import conduit_components for shared UI primitives.
- Extend TextToSpeechState with sentence data:
sentences, sentenceOffsets, activeSentenceIndex, and per-word
progress (wordStartInSentence, wordEndInSentence).
- Add provider callbacks wiring: onSentenceIndex and
onDeviceWordProgress handlers (hooked into TTS backend).
- Prepare sentence splitting and word-progress plumbing in the TTS
provider (prepares data used to drive the karaoke display).
This change improves UX by visually indicating the spoken sentence
and current word during TTS playback, aiding comprehension and
accessibility.
Introduce server TTS support and engine selection while keeping
device TTS as the default.
- Add new persistence keys for storing TTS engine and selected
server voice (ttsEngine, ttsServerVoiceId, ttsServerVoiceName).
- Extend TextToSpeechService to support two engines:
TtsEngine.device (FlutterTts) and TtsEngine.server (remote audio).
- Wire in an AudioPlayer and optional ApiService to fetch raw
audio bytes from the server and play them, with event hooks
mapped to existing lifecycle callbacks.
- Implement fallback to device TTS on server errors or empty
responses, and ensure player lifecycle (pause/stop/dispose)
is handled when using server engine.
- Allow engine and preferred voice to be configured before
initialization and updated at runtime via updateSettings.
This enables selecting a server-side voice and using a remote
TTS provider while preserving compatibility with the existing
device TTS implementation.
- Introduced new preference keys for TTS settings: voice, speech rate, pitch, and volume.
- Updated SettingsService to handle TTS settings and persist them.
- Enhanced AppSettings to include TTS-related properties.
- Implemented TTS settings UI in AppCustomizationPage, allowing users to select voice and adjust speech parameters.
- Added localization support for TTS settings in multiple languages.
- Integrated markdown conversion in TextToSpeechController to clean text before speech synthesis, ensuring only valid content is spoken.
- Updated VoiceCallService to utilize markdown conversion for responses, improving the clarity of spoken content.
- Enhanced VoiceCallPage to display cleaned text from markdown, providing a better user experience during voice interactions.
