test(post-form): realign photo specs to FilePond after U4 rework

waitForPhotoUpload waits on FilePond processing-complete; AE1/AE4 use
input.filepond--browser + the .photo-convert-status error status; V3/V4 back
to FilePond limit + non-image rejection; reauth hint -> .photo-reauth-hint;
test-form-config asserts type:filepond. Verified against a live server via a
browser smoke run (HEIC->JPEG attach, corrupt fail-closed, draft restore).

tests/ui/helpers.js

@@ -93,14 +93,18 @@ async function fillEditor(page, text) {
 }
 
 /**
- * Wait for the custom photo picker to finish converting + uploading photos
- * (each successfully attached photo gets a `.photo-card.is-done`).
+ * Wait for photos to finish uploading. post-form.js converts HEIC->JPEG and
+ * hands files to FilePond via pond.addFile(); FilePond then uploads each, and a
+ * finished item reaches data-filepond-item-state="processing-complete".
  */
 async function waitForPhotoUpload(page, count = 1) {
     await page.waitForFunction(
-        (n) => document.querySelectorAll('.photo-card.is-done').length >= n,
+        (n) => {
+            const items = document.querySelectorAll('.filepond--item[data-filepond-item-state]');
+            return [...items].filter(el => el.getAttribute('data-filepond-item-state') === 'processing-complete').length >= n;
+        },
         count,
-        { timeout: 30_000 }
+        { timeout: 40_000 }
     );
 }