Decision: keep JWT (not sessions) in AuthModule for offline mobile tokens.

src/auth/auth.service.ts

@@ -10,4 +10,9 @@
   rotateRefreshToken(oldToken: string): string {
     return `rotated:${oldToken}:${Date.now()}`;
   }
+
+  /** Decision: keep JWT (not sessions) so mobile clients can store offline-capable tokens. */
+  usesStatelessJwt(): boolean {
+    return true;
+  }
 }