feat: developer access permission gates webhooks/API keys/BYOK (v0.71.0)

Webhooks, self-serve API keys, and BYOK AI provider keys had zero
access gating -- any logged-in user, any tier. Adds users.isDeveloper
(boolean, admin-toggled in admin/users/[id] alongside role/tier),
checked via a single hasDeveloperAccess() (lib/permissions.ts) so a
future subscription-tier auto-grant is a one-line change there, not
a redesign across call sites.

requireDeveloper() (lib/api-auth.ts) wraps requireSession() with a
fresh isDeveloper check (same reasoning as requireAdmin re-querying
role: session.user's cookieCache can be up to 5 minutes stale) and
replaces requireSession in all 8 gated routes: webhooks CRUD +
deliveries + redeliver, api-keys CRUD, ai-keys CRUD.

Settings UI: the sidebar hides API Keys/Webhooks nav entries for
non-developers; those pages and the BYOK section of Settings -> AI
show a locked notice instead of the manager component when accessed
directly.

Migration grandfathers in anyone who already has a webhook, API key,
or BYOK key row -- ships as a new gate on existing features, not a
silent lockout of active integrations.

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

apps/web/app/(app)/settings/api-keys/page.tsx

@@ -3,8 +3,9 @@ import { headers } from "next/headers";
 import Link from "next/link";
 import { ExternalLink } from "lucide-react";
 import { auth } from "@/lib/auth/server";
-import { db, apiKeys, eq } from "@epicure/db";
+import { db, apiKeys, users, eq } from "@epicure/db";
 import { ApiKeysManager } from "@/components/settings/api-keys-manager";
+import { DeveloperLockedNotice } from "@/components/settings/developer-locked-notice";
 import { getMessages } from "@/lib/i18n/server";
 
 export const metadata: Metadata = {};
@@ -14,16 +15,20 @@ export default async function ApiKeysPage() {
   if (!session) return null;
   const m = getMessages((session.user as { locale?: string }).locale);
 
-  const keys = await db
-    .select({
-      id: apiKeys.id,
-      name: apiKeys.name,
-      scope: apiKeys.scope,
-      lastUsedAt: apiKeys.lastUsedAt,
-      createdAt: apiKeys.createdAt,
-    })
-    .from(apiKeys)
-    .where(eq(apiKeys.userId, session.user.id));
+  const dbUser = (await db.select({ isDeveloper: users.isDeveloper }).from(users).where(eq(users.id, session.user.id)).limit(1))[0];
+
+  const keys = dbUser?.isDeveloper
+    ? await db
+        .select({
+          id: apiKeys.id,
+          name: apiKeys.name,
+          scope: apiKeys.scope,
+          lastUsedAt: apiKeys.lastUsedAt,
+          createdAt: apiKeys.createdAt,
+        })
+        .from(apiKeys)
+        .where(eq(apiKeys.userId, session.user.id))
+    : [];
 
   return (
     <div className="space-y-8">
@@ -42,15 +47,18 @@ export default async function ApiKeysPage() {
             {m.settings.apiKeysPage.docsLink}
           </Link>
         </div>
-        <ApiKeysManager
-          initialKeys={keys.map((k) => ({
-            id: k.id,
-            name: k.name,
-            scope: k.scope,
-            lastUsedAt: k.lastUsedAt ? k.lastUsedAt.toISOString() : null,
-            createdAt: k.createdAt.toISOString(),
-          }))}
-        />
+        {!dbUser?.isDeveloper && <DeveloperLockedNotice message={m.settings.developerLockedNotice} />}
+        {dbUser?.isDeveloper && (
+          <ApiKeysManager
+            initialKeys={keys.map((k) => ({
+              id: k.id,
+              name: k.name,
+              scope: k.scope,
+              lastUsedAt: k.lastUsedAt ? k.lastUsedAt.toISOString() : null,
+              createdAt: k.createdAt.toISOString(),
+            }))}
+          />
+        )}
       </section>
     </div>
   );