Cross-platform distribution, UI improvements, and performance optimizations

- PyInstaller frozen sidecar: spec file, build script, and ffmpeg path resolver
  for self-contained distribution without Python prerequisites
- Dual-mode sidecar launcher: frozen binary (production) with dev mode fallback
- Parallel transcription + diarization pipeline (~30-40% faster)
- GPU auto-detection for diarization (CUDA when available)
- Async run_pipeline command for real-time progress event delivery
- Web Audio API backend for instant playback and seeking
- OpenAI-compatible provider replacing LiteLLM client-side routing
- Cross-platform RAM detection (Linux/macOS/Windows)
- Settings: speaker count hint, token reveal toggles, dark dropdown styling
- Loading splash screen, flexbox layout fix for viewport overflow
- Gitea Actions CI/CD pipeline (Linux, Windows, macOS ARM)
- Updated README and CLAUDE.md documentation

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -8,7 +8,7 @@ Desktop app for transcribing audio/video with speaker identification. Runs local
 - **ML pipeline:** Python sidecar process (faster-whisper, pyannote.audio, wav2vec2)
 - **Database:** SQLite (via rusqlite in Rust)
 - **Local AI:** Bundled llama-server (llama.cpp) — default, no install needed
-- **Cloud AI providers:** LiteLLM, OpenAI, Anthropic (optional, user-configured)
+- **Cloud AI providers:** OpenAI, Anthropic, OpenAI-compatible endpoints (optional, user-configured)
 - **Caption export:** pysubs2 (Python)
 - **Audio UI:** wavesurfer.js
 - **Transcript editor:** TipTap (ProseMirror)
@@ -40,7 +40,13 @@ docs/                   # Architecture and design documents
 - Database: UUIDs as primary keys (TEXT type in SQLite)
 - All timestamps in milliseconds (integer) relative to media file start
 
+## Distribution
+- Python sidecar is frozen via PyInstaller into a standalone binary for distribution
+- Tauri bundles the sidecar via `externalBin` — no Python required for end users
+- CI/CD builds on Gitea Actions (Linux, Windows, macOS ARM)
+- Dev mode uses system Python (`VOICE_TO_NOTES_DEV=1` or debug builds)
+
 ## Platform Targets
-- Linux (primary development target)
-- Windows (must work, tested before release)
-- macOS (future, not yet targeted)
+- Linux x86_64 (primary development target)
+- Windows x86_64
+- macOS aarch64 (Apple Silicon)