Pending bubbles that survive a reload (or post-redeploy refresh) without a
FileSystemFileHandle had no way to recover the original File bytes, so the
Retry button silently no-op'd: resumeUpload set state back to 'paused' with
no surfaced error, leaving the user stuck.
- transferStore: add reactive hasInMemoryFile Set mirroring liveUploadFiles.
setInMemoryRef helper keeps both in sync at every set/delete site
(startUpload, resumeUpload, onSuccess, remove). Persisted shape is unchanged.
- resumeUpload: when no blob is reachable (no in-memory File and no FS handle),
call setError with an actionable "File no longer available — discard and
re-upload" message instead of silently flipping back to 'paused'.
- Message.tsx: compute canRetry reactively from transfersForRow + hasInMemoryFile;
hide the Retry button when retry is infeasible. Discard remains.
- AttachmentProgress: optional error prop surfaces transfer.error.message via
title= on the failed-state ring for hover context.
- Tests: existing 3 resumeUpload tests now assert state==='failed' with the
actionable message; +2 new tests for hasInMemoryFile lifecycle (start/remove,
abort retains).
Jannis Braun