fix(recipes): preserve scroll position on filter, search, and folder-driven reloads

Five entry points that trigger recipe page reloads were not passing
preserveScroll: true, causing the page to snap back to top after
filtering, searching, or navigating folders — especially painful with
hundreds of recipes.

- RecipePageControls.resetAndReload() → refreshVirtualScroll() now
  passes { preserveScroll: true } (sidebar folder clicks/drag moves)
- FilterManager applyFilters/clearAllFilters → loadRecipes(true)
  changed to loadRecipes({ preserveScroll: true })
- SearchManager performSearch → loadRecipes(true) changed to
  loadRecipes({ preserveScroll: true })
- SettingsManager reloadContent → loadRecipes() changed to
  loadRecipes({ preserveScroll: true })

The normalizeLoadRecipesOptions boolean path always forces
preserveScroll: false — the object form is required to pass it.

static/js/managers/SearchManager.js

@@ -301,7 +301,7 @@ export class SearchManager {
       
       // Call the appropriate manager's load method based on page type
       if (this.currentPage === 'recipes' && window.recipeManager) {
-        window.recipeManager.loadRecipes(true); // true to reset pagination
+        window.recipeManager.loadRecipes({ preserveScroll: true });
       } else if (this.currentPage === 'loras' || this.currentPage === 'embeddings' || this.currentPage === 'checkpoints') {
         // For models page, reset the page and reload
         getModelApiClient().loadMoreWithVirtualScroll(true, false);