fix(subscriptions): address code review feedback

- Use shared _require_admin from admin_users in subscriptions API endpoint
- Remove unnecessary Alpine.js hidden-div workaround in pricing.html
- Replace fragile string replace for OCR page count with proper Jinja {:,} format
- Improve comment wording in upload quota cleanup code
- Extract _scalar_count() helper in subscription.py to reduce repetition
- Add aria-valuemin='0' to all progressbar elements in subscription/index templates

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

app/api/files.py

@@ -1303,7 +1303,8 @@ async def ui_upload(request: Request, db: DbSession, file: UploadFile = File(...
         try:
             check_upload_allowed(db, upload_owner_id, tier_id)
         except QuotaExceeded as qe:
-            # Clean up the already-saved file before rejecting
+            # Clean up the temporarily written file before returning the error
+            # to avoid consuming disk space for a rejected upload.
             if os.path.exists(target_path):
                 os.remove(target_path)
             raise HTTPException(