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/__tests__/resolve-user-key.test.ts

@@ -20,7 +20,7 @@ vi.mock("@epicure/db", () => ({
   and: vi.fn((...args) => args),
 }));
 
-const { getDefaultProviderWithKey, getModelConfigForUseCase, withUserKey } = await import("../resolve-user-key");
+const { getDefaultProviderWithKey, getModelConfigForUseCase, withUserKey, ByokDecryptError } = await import("../resolve-user-key");
 
 beforeEach(() => {
   vi.clearAllMocks();
@@ -74,15 +74,13 @@ describe("getDefaultProviderWithKey", () => {
     expect(config.apiKey).toBe("sk-from-site-settings");
   });
 
-  it("skips corrupted BYOK key and tries next provider", async () => {
+  it("throws ByokDecryptError instead of silently falling back on a corrupted BYOK key", async () => {
     mockUserAiKeysFindMany.mockResolvedValue([
       { provider: "openrouter", encryptedKey: "CORRUPT:NOT:VALID" },
       { provider: "openai", encryptedKey: encrypt("sk-valid") },
     ]);
 
-    const config = await getDefaultProviderWithKey("user1");
-    expect(config.provider).toBe("openai");
-    expect(config.apiKey).toBe("sk-valid");
+    await expect(getDefaultProviderWithKey("user1")).rejects.toThrow(ByokDecryptError);
   });
 });
 

apps/web/lib/ai/ai-error.ts

@@ -1,6 +1,7 @@
 import { NextResponse } from "next/server";
 import { APICallError } from "ai";
 import { checkAndIncrementTierLimit, refundAiCall, TierLimitError } from "@/lib/tiers";
+import { ByokDecryptError } from "@/lib/ai/resolve-user-key";
 
 /**
  * Maps an AI-call failure to a clean JSON response instead of letting the
@@ -23,6 +24,22 @@ export function aiErrorResponse(err: unknown): NextResponse {
   return NextResponse.json({ error: "AI request failed. Please try again." }, { status: 502 });
 }
 
+/**
+ * Resolves a BYOK/model config and converts a decrypt failure into a clean
+ * 400 response instead of letting it throw uncaught (or letting the caller
+ * silently fall back to the platform key/billing).
+ */
+export async function resolveAiConfigOrError<T>(resolve: () => Promise<T>): Promise<{ ok: true; data: T } | { ok: false; response: NextResponse }> {
+  try {
+    return { ok: true, data: await resolve() };
+  } catch (err) {
+    if (err instanceof ByokDecryptError) {
+      return { ok: false, response: NextResponse.json({ error: err.message }, { status: 400 }) };
+    }
+    throw err;
+  }
+}
+
 type QuotaResult<T> = { ok: true; data: T } | { ok: false; response: NextResponse };
 
 /**

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);
       }
     }
   }