feat: Implement audit logging and rate limiting middleware with SurrealDB integration

- Added audit logging middleware to track admin actions and save logs to SurrealDB.
- Introduced rate limiting middleware for public endpoints and authentication endpoints.
- Enhanced security headers middleware with nonce generation for CSP in development.
- Created utility functions for extracting real client IP addresses from headers.
- Updated Cargo.toml and Cargo.lock to include new dependencies.
- Added new schemas for audit logs and rate limiting in the entities module.
- Refactored permissions middleware to support new permission checks.

imphnen-entities/src/lib.rs

@@ -2,6 +2,7 @@ pub mod common_dto;
 pub mod error_dto;
 pub mod users;
 pub mod permissions;
+pub mod audit_log;
 
 // Re-export error type at root level for convenience
 pub use error_dto::error::Error;
@@ -25,3 +26,6 @@ pub use users::UsersDetailQueryDto;
 pub use permissions::PermissionsEnum;
 pub use permissions::PermissionsItemDto;
 pub use permissions::PermissionsQueryDto;
+
+// Explicit audit_log exports
+pub use audit_log::AuditLogSchema;