7ae6ab3ba8
GPU-arbiter safety layer for when automation, not just the dashboard, swaps models: - swap reservation lock (POST/GET/DELETE /api/swap/lock); 423-enforced in post_swap via a single-read gate, TTL-bounded, secret-token auth, human force-release override + dashboard banner - swap webhook (swap_complete/swap_failed) fired outside the swap lock, optional HMAC signature, configurable URL+secret - read-only schedule registry (GET/POST/DELETE /api/schedule) + dashboard panel New module image/app/coordination.py; docs/COORDINATION.md for consumers; 22 offline tests in test_coordination.py.