feat: Enhance validation and permissions handling across controllers

- Added `ValidatedJson` extractor for automatic JSON validation in `events_controller.rs`, `testimonials_controller.rs`, `mentors_controller.rs`, `gacha_items_controller.rs`, and `hackathon_controller.rs`.
- Replaced manual permission checks with `require_permissions!` and `require_auth!` macros in relevant controllers to streamline permission handling.
- Introduced `sanitization` utilities in `sanitization.rs` for improved input sanitization.
- Added `permission_macros.rs` to encapsulate permission checking logic and reduce boilerplate.
- Updated dependencies in `Cargo.toml` to include `serde_json` and `validator`.
- Implemented error handling improvements in `notification_service.rs` for better response management.

imphnen-iam/src/lib.rs

@@ -1,4 +1,5 @@
 pub mod v1;
+pub mod permission_macros;
 
 // Re-export core entity types used throughout the IAM module
 pub use imphnen_entities::{
@@ -71,6 +72,9 @@ pub use v1::{
     permissions_guard,
 };
 
+// Export permission macros
+pub use permission_macros::{check_permissions, check_authenticated};
+
 // Export IAM-specific types
 pub use v1::auth::{
     AuthRepository, AuthOtpSchema,