fe_comment v2: FE-user feedback tickets with summary, uploads and API

- Replace the v1 submit endpoint with a full JSON API under
  /api/fe-comment/ (state, feedback create/update/delete, uploads,
  summary notes/recipients, submit), guarded by frontend login and a
  configurable FE user group; unauthorized callers get {"allowed":false}
- New models: tx_fecomment_summary (one open ticket per user, status
  open/sent) and tx_fecomment_feedback (url, RTE note, FAL attachments),
  both editable in the backend on the ticket storage page
- FeedbackApiMiddleware registered after frontend authentication (the
  frontend.user attribute does not exist earlier); uploads land in
  fileadmin/fe_comment/summary-<uid>/ with mime/extension check, 20 MB cap
- Submit sends one HTML mail (author block, items with attachment links,
  reply-to = FE user mail) to selected recipients with mailTo fallback,
  then closes the summary
- felogin wired React-compatible: felogin.pid=520 plus headless FeLogin
  JSON templates via site settings - felogin v14 and EXT:headless both
  claim templateRootPaths.10, the felogin.view.* settings feed exactly
  that index, so the structured JSON form (incl. __RequestToken) wins
- Read the sys_file_reference insert id before syncAttachmentCount():
  DBAL throws "no identity value" once the count UPDATE has run
- migrations: drop_fecomment_tables.php (repairs the no-uid tables,
  only drops when empty), check_feuser.php (login diagnosis),
  fec_login_test.sh / fec_api_test.sh (curl chains incl. CSRF token flow)

packages/fe_comment/ext_conf_template.txt

@@ -15,3 +15,12 @@ subject = Page feedback
 
 # cat=output//10; type=boolean; label=JSON output (headless mode): 1 = TYPO3 injects nothing, the front end embeds <script src="/api/fe-comment/widget.js"> itself (SPA / React). 0 = classic TYPO3 site, the widget script is injected into every rendered page automatically.
 jsonOutput = 1
+
+# cat=access//10; type=string; label=FE user group (uid): Only logged-in frontend users in this group see and use the widget. 0 = any logged-in user.
+feUserGroup = 0
+
+# cat=mail//50; type=string; label=Selectable recipients: who the feedback can be sent to, as "Label <mail@example.com>" entries separated by semicolons. Empty = only the Mail to address above.
+recipients =
+
+# cat=basic//20; type=string; label=Storage pid: page/folder uid the feedback records are stored on (backend visibility). 0 = root.
+storagePid = 0