fix: restore admin role in User type, use image logo

- Add "admin" back to User.role union to fix backend TS build
- Replace SVG PeonyIcon with logo.png image in Logo component

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/types/src/index.ts

@@ -21,7 +21,7 @@ export interface User {
   slug: string | null;
   description: string | null;
   tags: string[] | null;
-  role: "model" | "viewer";
+  role: "model" | "viewer" | "admin";
   is_admin: boolean;
   /** UUID of the avatar file */
   avatar: string | null;