GitLab

Features:
- Background model discovery via /v1/models (ModelRefresher)
- Chat playground with SSE streaming + per-message latency metrics
- Benchmark scheduler with concurrent runs + live grid UI
- Diagnostics panel with vendor-specific probes (Prometheus/JSON)
- Dashboard with stats, server-kind breakdown, recent activity
- Settings page with dark mode toggle (Alpine.js + localStorage)
- 12 Leaf templates covering all surfaces
- M07-M09 migrations for message metrics, conversation model_id, benchmark metadata

Fixes:
- Split SQLite multi-column ALTER TABLE into sequential calls
- Register all migrations in test setup (M07-M09)

Tests: 44 passing, 0 failures