Refactor handlers and OpenAPI documentation for improved readability and consistency

- Reorganized imports in health, notifications, social, thoughts, and users handlers for clarity.
- Updated function signatures in handlers to improve readability by aligning parameters.
- Enhanced JSON response formatting in notifications and thoughts handlers.
- Improved error handling in user-related functions.
- Refactored OpenAPI documentation to maintain consistent formatting and structure.
- Cleaned up unnecessary code and comments across various files.
- Ensured consistent use of `Arc` for shared state in AppState and WorkerHandlers.

crates/worker/src/handlers.rs

@@ -1,6 +1,6 @@
-use std::sync::Arc;
 use application::services::{FederationEventService, NotificationEventService};
 use domain::{errors::DomainError, events::DomainEvent};
+use std::sync::Arc;
 
 pub struct NotificationHandler {
     pub service: Arc<NotificationEventService>,