- Introduced new `entity_operations.cc` and `entity_operations.h` files to handle the insertion of entrances, exits, sprites, and items in the overworld editor.
- Updated `map_properties.cc` to include a context menu for entity insertion, allowing users to add various entities directly from the canvas.
- Enhanced `overworld_editor.cc` to manage entity insertion callbacks and streamline the editing process.
Benefits:
- Improves the functionality of the overworld editor by enabling direct manipulation of entities.
- Provides a more intuitive user experience with context-sensitive menus for entity operations.
