add platform pages

frontend/src/app.d.ts

@@ -5,6 +5,10 @@ declare global {
 		interface Locals {
 			user: SessionUser | null;
 			pbToken: string | null;
+			// Platform-admin (superuser dashboard) session — set from the
+			// platform_session cookie in hooks.server.ts. Separate from the
+			// fam user session; only /admin consumes it.
+			platformAdmin: boolean;
 		}
 	}
 }