- Added `ProxyHostInfo`, `ProxyHostCreateInfo`, and `UpdateProxyHostInfo` structs to manage proxy host data.
- Created `ProxyService` and `ProxyServiceImpl` for handling proxy host operations including create, read, update, and delete.
- Implemented `LocationService` and `LocationServiceImpl` for managing locations associated with proxy hosts.
- Introduced database transaction handling for creating proxies and locations.
- Added tests for all service methods to ensure functionality and correctness.