security: fix full audit findings (v0.32.0)

Full list of the audit's confirmed findings and their fixes:

- Stored XSS via unescaped JSON-LD on the public recipe page
  (app/r/[id]/page.tsx) — escape < before injecting.
- CSP allowed unsafe-eval in production — now dev-only (Next prod
  never eval()s; only its HMR does).
- avatarUrl accepted any URL with no ownership check — now takes an
  avatarKey issued by avatar-presign, validated server-side, same
  pattern as recipe/review photos.
- No session revocation on password change/reset — both now revoke
  other sessions (revokeOtherSessions: true, revokeSessionsOnPasswordReset).
- Rate-limit bypass via spoofable X-Forwarded-For — take the last
  (proxy-appended) hop instead of the first (client-supplied) one,
  matching the single-Traefik-hop topology.
- Webhook signing secrets stored plaintext — now AES-256-GCM
  encrypted like every other secret in this app, with a legacy-
  plaintext fallback for pre-existing rows (bare hex has no ":", our
  ciphertext format always does).
- Better Auth's own rate limiter defaulted to in-memory storage,
  ineffective across replicas — now backed by the same Redis as
  lib/rate-limit.ts (secondaryStorage), with storeSessionInDatabase
  explicit so session storage itself doesn't move as a side effect.
- Presigned upload URLs didn't bind the declared file size to the
  actual upload, letting a client under-declare size (and quota
  charge) then PUT an arbitrarily large object — switched to S3
  presigned POST with a signed content-length-range condition,
  enforced by the storage server itself.
- generateMetadata() on the recipe page skipped the visibility
  filter the page body uses, leaking a private recipe's title via
  <title> to any signed-in user with the id.
- Block/unblock had no rate limit, unlike follow/unfollow.
- AI quota was charged even when a user's own BYOK key was used
  (their own credentials/billing) — added an isByok flag through
  the config-resolution chain and skip the charge when set. Also
  wired BYOK into generate/generate-from-idea/translate/import-url,
  which never looked it up at all before.

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

apps/web/components/social/cooked-it-review.tsx

@@ -9,6 +9,7 @@ import { Button } from "@/components/ui/button";
 import { Textarea } from "@/components/ui/textarea";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
 import { getPublicUrl } from "@/lib/storage";
+import { uploadToPresignedPost } from "@/lib/upload-client";
 import { cn } from "@/lib/utils";
 
 type Review = {
@@ -93,8 +94,12 @@ export function CookedItReview({
         toast.error(t("reviewPhotoFailed"));
         return;
       }
-      const { url, key } = (await res.json()) as { url: string; key: string };
-      await fetch(url, { method: "PUT", body: file, headers: { "Content-Type": file.type } });
+      const { url, fields, key } = (await res.json()) as { url: string; fields: Record<string, string>; key: string };
+      const uploaded = await uploadToPresignedPost(url, fields, file);
+      if (!uploaded) {
+        toast.error(t("reviewPhotoFailed"));
+        return;
+      }
       setPhotoKey(key);
       setPreview(URL.createObjectURL(file));
     } finally {