feat(frontend) : add portal pages, update auth middleware and DTOs for client portal

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/services/dto/user-data.ts

@@ -1,10 +1,12 @@
+import type { Project } from './project'
+
 export type UserData = {
     id: number
     '@id'?: string
     username: string
     roles: string[]
-    client?: { '@id'?: string; id: number; name: string } | null
-    allowedProjects?: { '@id'?: string; id: number; name: string }[]
+    client?: { id: number; name: string } | null
+    allowedProjects?: Project[]
 }
 
 export type UserWrite = {