Background discovery reliability and diagnostics
- Keeps confirmed-result acceleration on interactive stream requests while background warming continues normal discovery.
- Adds a per-account/provider circuit breaker after repeated warm-up failures; interactive searches are unaffected.
- Adds live Database diagnostics for attempts, success/failure counts, skipped work, latency, last success/error, and suppression state.
- Fixes MotoGP Free Practice and FP1-FP4 location parsing generically, including the malformed Aragon Free alias case.
Validation: 108 unit tests passed plus full JavaScript syntax and module-load smoke checks.