Fixes:
- Streaming was bypassed for all requests (system prompt auto-inject made
messages.size always > 1). Stream=true now routes directly to generateStreaming
before multi-turn check
- LiteRTModel: add Mutex to serialize Engine calls (not thread-safe)
New features:
- Settings card: temperature slider, max tokens, agent system prompt toggle
(all saved to SharedPreferences, applied on server start)
- Active request indicator: "⚡ Processing request…" shown in status card
while inference is running
- onActiveRequest callback from AIApiServer → ApiServerService → MainActivity
Co-Authored-By: Claude Sonnet 4.6 <[email protected]>
