Adopt HTTP status codes for API response handling #523
Description
Describe the feature
The API currently wraps all responses inside an ApiResponse struct containing a success: bool field and an optional payload. This pattern increases complexity for clients, requiring nested Option matching and custom parsing logic.
To simplify usage and align with REST best practices, consider removing the wrapper and relying on standard HTTP status codes to indicate success or failure. Errors can be returned as structured JSON responses, while successful calls should return flat, typed response bodies directly.
Additional context
No response