insights: Poll insight when data is backfilling
Created by: chwarwick
Adds a feature flag that allows the UI poll for updates when an insight is currently backfilling.
closes #35479 (closed)
Test plan
Verified with feature flag on/off that insights render properly on standalone and dashboard pages. Verified polling stops when backfill is complete Verified polling does not take place with just in time insights
App preview:
Check out the client app preview documentation to learn more.