* feat(tts/stt): add API key support for OpenAI-compatible custom providers
## Problem
Custom (OpenAI-compatible) TTS/STT provider in Voice Settings has no way to
pass an API key or bearer token. Many self-hosted or third-party compatible
servers require authentication, making them unreachable from OpenChamber.
The server-side TTS route already accepts an `apiKey` parameter, but the
frontend never sends it. The STT route hardcodes `'not-required'`.
## Implementation
- Add `openaiCompatibleApiKey` to Zustand config store, persisted to localStorage
- Add API Key input field in VoiceSettings.tsx under the custom provider section
- Wire `openaiCompatibleApiKey` through useServerTTS to the TTS backend
- Add `apiKey` field to AudioStreamConfig for STT, forwarded as X-API-Key header
- Update server STT route to accept and forward X-API-Key to transcribeAudio
- Update stt.js to use client-provided apiKey before falling back to env var
## Files changed
- packages/ui/src/stores/useConfigStore.ts
- packages/ui/src/components/sections/openchamber/VoiceSettings.tsx
- packages/ui/src/hooks/useServerTTS.ts
- packages/ui/src/hooks/useBrowserVoice.ts
- packages/ui/src/lib/voice/audioStreamService.ts
- packages/web/server/lib/tts/routes.js
- packages/web/server/lib/tts/stt.js
* feat(tts/stt): add separate API key support for custom TTS and STT providers
## Problem
Custom (OpenAI-compatible) TTS and STT providers in Voice Settings have no way
to pass API keys. Many self-hosted or third-party compatible servers require
authentication, making them unreachable from OpenChamber Desktop (Electron).
## Implementation
- Add `openaiCompatibleApiKey` for TTS (persisted to localStorage, passed in JSON body)
- Add `sttApiKey` for STT (persisted to localStorage, passed via Authorization: Bearer header)
- Two independent keys: TTS and STT are configured separately
- STT authentication follows OpenAI standard (Authorization: Bearer <token>)
- TTS authentication follows existing pattern (apiKey in JSON body)
- Backend STT route extracts bearer token from Authorization header
- Backend STT service prefers client-provided key over OPENAI_API_KEY env var
## Fixes
- Fixed P1: ConfigStore interface now declares setOpenaiCompatibleApiKey setter
- STT API key is only forwarded when sttProvider === 'server' (not leaked to other providers)
## Files changed (7)
- packages/ui/src/stores/useConfigStore.ts
- packages/ui/src/components/sections/openchamber/VoiceSettings.tsx
- packages/ui/src/hooks/useServerTTS.ts
- packages/ui/src/hooks/useBrowserVoice.ts
- packages/ui/src/lib/voice/audioStreamService.ts
- packages/web/server/lib/tts/routes.js
- packages/web/server/lib/tts/stt.js
* fix: refresh server STT callback when API key changes
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Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>
