feat(selfhost): start full updates from administration

backend/src/utils/requireSystemAdmin.ts

@@ -0,0 +1,18 @@
+import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
+import { eq } from "drizzle-orm";
+import { authUsers } from "../../db/schema/auth_users";
+
+export async function requireSystemAdmin(server: FastifyInstance, req: FastifyRequest, reply: FastifyReply) {
+    if (!req.user?.user_id) {
+        reply.code(401).send({ error: "Unauthorized" });
+        return null;
+    }
+    // Read the current global role; tenant roles and stale JWT claims do not grant access.
+    const [user] = await server.db.select({ id: authUsers.id, email: authUsers.email, is_admin: authUsers.is_admin })
+        .from(authUsers).where(eq(authUsers.id, req.user.user_id)).limit(1);
+    if (!user?.is_admin) {
+        reply.code(403).send({ error: "Admin access required" });
+        return null;
+    }
+    return user;
+}