docs(36): auto-generated context (discuss skipped)

.planning/phases/36-voice-pipeline-foundation/36-CONTEXT.md

@@ -0,0 +1,73 @@
+# Phase 36: Voice Pipeline Foundation - Context
+
+**Gathered:** 2026-04-04
+**Status:** Ready for planning
+**Mode:** Auto-generated (discuss skipped via workflow.skip_discuss)
+
+<domain>
+## Phase Boundary
+
+The transport-agnostic voice pipeline is live and callable from any consumer — web chat, Telegram, or future integrations — with correct audio transcoding, voice mode flag propagation, and dual output formatting baked in from the start.
+
+Requirements: VPIPE-01, VPIPE-02, VPIPE-03, VPIPE-04, VPIPE-05, VPIPE-06
+
+</domain>
+
+<decisions>
+## Implementation Decisions
+
+### Claude's Discretion
+All implementation choices are at Claude's discretion — discuss phase was skipped per user setting. Use ROADMAP phase goal, success criteria, and codebase conventions to guide decisions.
+
+Key research findings to incorporate:
+- VoicePipelineService as server-side service: `transcribe(buffer, format)`, `synthesize(text, voiceId?)`, `formatForVoice(text)`
+- Move `/transcribe` from `chat-files.ts` to new `voice.ts` route to reduce rebase conflict surface
+- Use `ffmpeg-static ^5.2.0` (NOT archived fluent-ffmpeg) for WebM→WAV and OGG→WAV transcoding
+- Use `execFile` (not `exec`) for CLI subprocess calls — prevents shell injection
+- Wrap CLI calls (`piper`, `ffmpeg`) in `Promise.race([call, timeout(8000)])` for graceful degradation
+- Voice mode flag must survive: client → Express → message persistence → agent session codec
+- Dual output: prompt engineering requests `SPOKEN: [prose]` + `DETAILED: [markdown]` with post-processing strip as fallback
+- nexus-settings schema extension: `voiceMode: "text" | "voice_input" | "full_voice"`, optional `telegramToken`
+- No DB migrations — all state in existing JSONB fields and file-backed JSON
+
+</decisions>
+
+<code_context>
+## Existing Code Insights
+
+### Reusable Assets
+- `server/src/routes/chat-files.ts` — existing `/transcribe` endpoint with whisper-cpp/openai-whisper cascade
+- `server/src/services/nexus-settings.ts` — file-backed JSON with Zod validation
+- `packages/shared/src/validators/chat.ts` — Zod chat message validators
+- `packages/shared/src/types/chat.ts` — ChatMessage type definitions
+- `ui/src/components/VoiceRecordButton.tsx` — MediaRecorder API (client-side)
+- `ui/src/components/TtsButton.tsx` — @mintplex-labs/piper-tts-web WASM
+- `ui/src/hooks/usePiperTts.ts` — browser TTS hook
+
+### Established Patterns
+- Express route files in `server/src/routes/`
+- Service files in `server/src/services/`
+- Zod validators in `packages/shared/src/validators/`
+- Routes mounted in `server/src/app.ts`
+- File-backed settings via nexus-settings service
+
+### Integration Points
+- `server/src/app.ts` — mount new voice routes
+- `packages/shared` — extend chat message types with voiceMode field
+- `server/src/services/nexus-settings.ts` — extend schema for voiceMode and telegramToken
+
+</code_context>
+
+<specifics>
+## Specific Ideas
+
+No specific requirements — discuss phase skipped. Refer to ROADMAP phase description and success criteria.
+
+</specifics>
+
+<deferred>
+## Deferred Ideas
+
+None — discuss phase skipped.
+
+</deferred>