feat(vlm): sort versions by newest first in VLM view, with disabled sort dropdown

When viewing all versions of a model (VLM mode via 'x versions' button):
- Backend always sorts by version ID descending, ignoring current sort_by
- A temporary 'Newest version first' option is injected into the sort
  dropdown (removed on exit, not a permanent option)
- The sort dropdown is disabled (greyed out) while VLM is active
- On clearing VLM, the previous sort preference is restored and the
  dropdown re-enabled
- Handles stale VLM state (e.g. after page reload with leftover session)
- Covers all three model page types: loras, checkpoints, embeddings

Also fixes review nits:
- Correct i18n call pattern (defaultValue in options object)
- Shared _restoreSortAfterVlm() helper to avoid triple duplication

py/services/base_model_service.py

@@ -111,6 +111,12 @@ class BaseModelService(ABC):
                 item for item in sorted_data
                 if self._extract_model_id(item) == civitai_model_id
             ]
+            # VLM mode: always sort by version ID descending (newest version first),
+            # regardless of the current sort_by preference.
+            sorted_data.sort(
+                key=lambda x: self._extract_version_id(x) or 0,
+                reverse=True,
+            )
 
         # Optionally group by civitai modelId, showing only the latest version per model
         dedup_lost = 0