When a public image's thumb_url or url fails to load, the fileupload
field fetches its preview once through the authenticated thumb route
(session key in the header) and shows it from an object URL, revoked
when the item is forgotten and on unmount. The preview is reported as
unavailable only when that fetch or the object-URL image fails too.
Protected fields behave as before.
Keep form save behind in-flight uploads, make retries idempotent via X-Upload-Id, cap remaining JSON bodies, and surface pending pivot type errors instead of zeroing them.
Co-authored-by: Cursor <cursoragent@cursor.com>
- sessionKey.ts: one 32-byte base64url key per form mount, sent only in headers
- api/files.ts: FileRoutes over the record and child file routes, XHR upload with progress, 401 refresh and retry
- FileuploadField and FileCaptionModal per UI-SPEC section 3: dropzone, image grid, rows, per-item states, client pre-checks, reorder, protected previews
- FormView provides FORM_SESSION, counts pending changes as dirty and sends X-Session-Key on create and update
- fileupload lang keys in en and pl, admin-spa docs note, deferred smoke test, rebuilt dist
