feat(ui): show version count in group-by-model cards, add versions_count sort, no-reload VLM

- group_by_model dedup now counts versions per group and attaches
  version_count; respects update_flag_strategy (same_base) by
  sub-grouping on base_model
- Card footer shows clickable 'x versions' link instead of version
  name when grouped (hides HIGH/LOW badges); clicking triggers
  View Local Versions without page reload
- Added 'Local Versions' sort option (versions_count), auto-hidden
  when group_by_model is off
- Sort preference is saved/restored separately for normal and
  grouped modes
- VLM flow (triggerVlmView, clearCustomFilter) uses resetAndReload()
  via API instead of window.location.reload()
- Fixed cache mutation bug: version_count is now set on a shallow
  copy, not the cached dict, preventing stale version_count leaking
  into VLM responses
- i18n: all 9 locale files translated

static/js/managers/SettingsManager.js

@@ -2018,6 +2018,10 @@ export class SettingsManager {
             }
 
             if (settingKey === 'show_only_sfw' || settingKey === 'blur_mature_content' || settingKey === 'group_by_model') {
+                // Save/restore sort preference when toggling group_by_model
+                if (settingKey === 'group_by_model' && window.pageControls?.onGroupByModelToggled) {
+                    window.pageControls.onGroupByModelToggled(value);
+                }
                 this.reloadContent();
             }