🔐 [security fix description] Implement strict JWT, OAuth2 & RBAC security layer

[beginwebdev2002]

🔐 [security fix description]\n\n🎯 What\nImplemented a bulletproof security layer for VIP data protection. Includes Google OAuth2 integration and strict JWT access/refresh token rotation. Backend is secured via strict RolesGuard and JwtAuthGuard, while frontend is secured via AuthInterceptor and explicit Auth/Admin Guards. \n\n⚠️ Risk\nUnsecured or improper role validation exposes VIP data to unauthenticated or unauthorized users, particularly bypassing the admin portal or API endpoints without proper token checks.\n\n🛡️ Solution\n1. Added strict backend global guarding with JwtAuthGuard and RolesGuard.\n2. Built HTTPOnly cookie-based refresh token rotation via POST /auth/refresh.\n3. Defined Google OAuth2 login strategies.\n4. Configured AuthInterceptor in Angular for seamless 401 handling, queueing, and Bearer token injection.

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PR created automatically by Jules for task 432179211790035832 started by @beginwebdev2002

[google-labs-jules]

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