ci: fast checks per PR, batch heavy builds to main/nightly/release - #6921

Bugbot Analysis Progress (3m 37s elapsed)

✅ Gathered PR context (12s)
✅ Completed bug detection (3m 25s)
✅ Posted analysis results (1s)

Final Result: Bugbot completed review - no issues found! ✅

Request ID: serverGenReqId_07cfd778-35d2-4e81-8731-abf4d3bee870