- Add capabilities.test.ts (18 tests) for supportsAudioInput()
- Add 15 audio tests to media.test.ts (hasAudio, stripAudioParts, attachmentToAudioSource)
- Add estimateAudioTokens() to tokens.ts (base64→bytes→duration→tokens)
- Update estimateMessageTokens() to include audio content parts
- Add 5 audio token tests to tokens.test.ts
- Add supports_audio config override to model schema
- Wire supports_audio from tier config through routing to capability check
Total tests: 1369 (was 1331, +38 audio-related)
- Create capabilities.ts with supportsAudioInput() detection
- Gemini, OpenAI, and GitHub Models get native audio passthrough
- Anthropic, Bedrock, Ollama, llama.cpp fall back to Whisper transcription
- routing.ts now checks model capability before deciding to transcribe
- Audio attachments are stripped for non-native models (only transcript text passed)
- Remove deprecated audioConfig from createMessageRouter deps (read from config.audio)
William Valentin