fix: audit fixes — tier-quota bypass, webhook SSRF, auth hardening, pagination, a11y

Full audit (bugs/UI-UX/backend/feature-gap) turned up a money-leak AI quota
bypass, webhook SSRF, and a long tail of missing pagination/auth/a11y work.
Fixes land together since HANDOFF.md tracked them as one backlog.

- AI routes charge tier quota before generating; nutrition POST is author-only
- Webhook dispatch re-validates URL per delivery (SSRF/DNS-rebinding), treats
  redirects as failures; recipe.published now actually dispatches
- New indexes/unique constraints on recipes, meal-planning, comments FK cascade
- Recipe PUT/restore snapshot only inside the transaction, after validation
- Recipe DELETE cleans up S3 objects (recipe + review photos)
- Optimistic UI (favorite/star/follow/shopping-list) rolls back on failure
- Upload presign enforces file size cap + per-tier storage quota
- Route-level loading/error/not-found states across (app), admin, and root
- middleware.ts guards (app)/admin; requireAdmin checks DB role, not cached
  session; rate limiting applied to both session and API-key branches,
  bucketed per key; Stripe webhook dedupes by event id
- Pagination added to recipes, feed, profile, comments, pantry, admin tables
- Nav shows real avatar + profile link + dark-mode toggle; destructive actions
  standardized on AlertDialog
- Unsaved-changes guard + real ingredient/step validation on recipe form;
  canonical /recipes/[id] used in-app; next/image migration; aria-labels and
  alt text across icon buttons, avatars, recipe photos
- packages/api-types removed (zero callers, too drifted to safely rewire);
  openapi.ts and ai-keys error shape drift fixed; BYOK decrypt failures now
  surface instead of silently falling back to the platform key

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/web/lib/ai/resolve-user-key.ts

@@ -5,6 +5,20 @@ import type { AiConfig, AiProvider } from "./factory";
 
 export type ModelUseCase = "text" | "vision" | "mealPlan";
 
+/**
+ * Thrown when a user's saved BYOK key exists but fails to decrypt (e.g. the
+ * encryption secret rotated, or the stored ciphertext is corrupt). Callers
+ * must surface this to the user instead of silently falling back to the
+ * platform key — otherwise the user believes their own key/billing is being
+ * used when it is not.
+ */
+export class ByokDecryptError extends Error {
+  constructor(public readonly provider: string) {
+    super(`Failed to decrypt saved API key for provider "${provider}". Please re-enter it in Settings.`);
+    this.name = "ByokDecryptError";
+  }
+}
+
 export async function withUserKey(userId: string, config: AiConfig): Promise<AiConfig> {
   const provider = config.provider;
   if (!provider) return config;
@@ -19,7 +33,7 @@ export async function withUserKey(userId: string, config: AiConfig): Promise<AiC
     const apiKey = decrypt(row.encryptedKey);
     return { ...config, apiKey };
   } catch {
-    return config;
+    throw new ByokDecryptError(provider);
   }
 }
 
@@ -56,7 +70,7 @@ export async function getDefaultProviderWithKey(userId: string): Promise<AiConfi
       try {
         return { provider: p, apiKey: decrypt(row.encryptedKey) };
       } catch {
-        continue;
+        throw new ByokDecryptError(p);
       }
     }
   }