Follow-up to the salvaged commit: instead of a new resolver component in
fallback.tsx (a second copy of MarkdownImageContent's resolve/cancel
effect), render the activity image with the existing MarkdownImage. It
already owns the local/remote file-bridge resolution (readFileDataUrl
locally, profile-scoped /api/fs/read-data-url on a remote gateway), the
loading and "Couldn't load" states, and the shared lightbox.
Rendered regression: a completed vision_analyze row with a text-only
native-vision receipt shows its disclosure, resolves the image through
the right bridge for the connection mode, and opens the lightbox.
Docs: mention expanding an image-bearing activity row.
9e4b10da41