Split bootstrap endpoint into slow-changing (1h TTL: BIS rates,
minerals, sectors, etc.) and fast-changing (10min TTL: earthquakes,
outages, macro signals, etc.) tiers via ?tier=slow|fast query param.
Frontend fetches both tiers in parallel with shared 800ms timeout.
Partial failure is graceful — panels fall through to individual RPCs.
Backward compatible: no ?tier= param returns all keys at s-maxage=600.
Also removes orphaned ucdpEvents key (no getHydratedData consumer).
2e93e0e8ed