feat(recipes): remove deprecated Repair Metadata feature

The recipe "Repair Metadata" action has been marked Deprecated in the UI
for a while and cannot reliably recover recipes imported from CivitAI URLs
whose REST meta has no resources/hashes and whose image has no embedded
metadata (e.g. CivitAI-only generation data). Drop the feature end to end.

Backend:
- remove repair routes (repair, cancel-repair, recipe/{id}/repair,
  repair-bulk, repair-progress) and their handler mappings/methods
- remove RecipeScanner repair_all_recipes / repair_recipe_by_id /
  _repair_single_recipe and REPAIR_VERSION
- remove WebSocketManager recipe-repair progress channel
- drop repair_version column from the persistent recipe cache
- rematch mutual-exclusion now only checks rematch

Frontend:
- remove repair entries from per-recipe, bulk and global context menus
- remove repairRecipe / repairSelectedRecipes / repairRecipes + cancelRepair
  and the repairBulk API client method/endpoint
- drop recipe-repair i18n keys (synced across locales; doctor keys kept)

Tests/docs: delete test_recipe_repair.py, update scaffolding/routes/ws/
persistent-cache/integration tests and i18n guideline examples.

static/js/components/ContextMenu/RecipeContextMenu.js

@@ -93,10 +93,6 @@ export class RecipeContextMenu extends BaseContextMenu {
                 // Download missing LoRAs
                 this.downloadMissingLoRAs(recipeId);
                 break;
-            case 'repair':
-                // Repair recipe metadata
-                this.repairRecipe(recipeId);
-                break;
             case 'rematch':
                 // Rematch recipe resources to local models
                 this.rematchRecipe(recipeId);
@@ -297,44 +293,6 @@ export class RecipeContextMenu extends BaseContextMenu {
         }
     }
 
-    // Repair recipe metadata
-    async repairRecipe(recipeId) {
-        if (!recipeId) {
-            showToast('recipes.contextMenu.repair.missingId', {}, 'error');
-            return;
-        }
-
-        try {
-            showToast('recipes.contextMenu.repair.starting', {}, 'info');
-
-            const response = await fetch(`/api/lm/recipe/${recipeId}/repair`, {
-                method: 'POST'
-            });
-            const result = await response.json();
-
-            if (result.success) {
-                if (result.repaired > 0) {
-                    showToast('recipes.contextMenu.repair.success', {}, 'success');
-                    const detailResponse = await fetch(`/api/lm/recipe/${recipeId}`);
-                    if (detailResponse.ok) {
-                        const updatedRecipe = await detailResponse.json();
-                        const filePath = this.currentCard?.dataset?.filepath;
-                        if (filePath && state.virtualScroller) {
-                            state.virtualScroller.updateSingleItem(filePath, updatedRecipe);
-                        }
-                    }
-                } else {
-                    showToast('recipes.contextMenu.repair.skipped', {}, 'info');
-                }
-            } else {
-                throw new Error(result.error || 'Repair failed');
-            }
-        } catch (error) {
-            console.error('Error repairing recipe:', error);
-            showToast('recipes.contextMenu.repair.failed', { message: error.message }, 'error');
-        }
-    }
-
     async rematchRecipe(recipeId) {
         if (!recipeId) {
             showToast('toast.recipes.rematchFailed', { message: 'Missing recipe ID' }, 'error');