- Root cause confirmed = mechanism (ii): ['me'] staleness, NOT a backend linking gap
(upsertUser claim preserves users.id → credential stays linked → DB needsProviderSetup=false)
- SetupBanner ['me'] query staleTime 5min → 0 so a pre-claim stale cache entry is
refetched on mount; banner hides once needsProviderSetup resolves false
- App.tsx boot ['me'] staleTime also set to 0 (committed with Task 1) for the same reason
- Add SetupBanner.test.tsx regression: absent when false, present (no dismiss) when true,
stale-cache refetch hides banner; success-only dismissal contract preserved (no X button)
- Log pre-existing PWA lint errors (SetupPage.test.tsx, setupClient.contract.test.ts) to deferred-items.md
