AI provider:
- Extract configureAIProvider() from saveSettings for reuse
- Call it on app startup after sidecar is ready (was only called on Save)
- Call it after first-time sidecar download completes
- Sidecar now receives correct Ollama URL/model immediately
Video extraction:
- Hide ffmpeg console window on Windows (CREATE_NO_WINDOW flag)
- Show "Extracting audio from video..." overlay with spinner during extraction
- UI stays responsive while ffmpeg runs
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>