Previous fix (2139ea8) caused regression: staleTime:0 nuked cache on
every mount, isLoadingIncoming disabled buttons during cold-cache fetch.
Changes:
- Remove staleTime:0 (keep refetchOnMount:'always' for background refresh)
- Revert button gate to pendingRequestIds.has() only (no is_read gate)
- Remove isLoadingIncoming from disabled prop and spinner condition
- Add 409-as-success handling to ConnectionRequestCard (People tab)
- Use axios.isAxiosError() instead of err:any in all 3 catch blocks
- Add markRead() call to 409 branch so notifications clear properly
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>