fix(uploads): retry failed files and report full storage

packages/i18n/locales/en/admin.json

@@ -270,6 +270,7 @@
     "failed_some_many": "{{count}} files did not upload — their space is reserved, you can continue.",
     "failed_some_other": "{{count}} files did not upload — their space is reserved, you can continue.",
     "retry_failed": "Continue upload",
+    "retry_file": "Retry upload of {{name}}",
     "uploading_now": "Uploading…",
     "go_mine": "My uploads →",
     "more": "Upload more",

packages/i18n/locales/en/errors.json

@@ -80,6 +80,7 @@
     "update_unavailable": "Update is unavailable"
   },
   "uploads": {
+    "storage_full": "The server has no space left for uploads. Ask an administrator to free up space, then retry the upload.",
     "queue_full": "The upload queue is full",
     "user_quota_full": "Your upload queue limit is exceeded",
     "too_large": "The file is larger than allowed",