- Introduced LoadedCapability class to manage plugin capabilities.
- Updated load_plugin function to discover and load capabilities alongside handlers.
- Enhanced Peer class to handle remote provided capabilities during initialization.
- Added tests for capability registration and invocation in legacy plugins.
- Improved MessageChain and message component handling in legacy plugins.
- Added comprehensive tests for legacy plugin integration and compatibility.
- Updated protocol messages to include provided capabilities in initialization.
- Enhanced top-level module imports to include capability-related functions.
- Added integration tests for the runtime module covering subprocess lifecycle, concurrency, and real-world scenarios in `test_runtime_integration.py`.
- Updated existing test files to include a blank line after module docstrings for consistency.
- Enhanced `test_protocol_legacy_adapter.py` with additional assertions for message output.
- Modified `test_transport.py` to use concrete transport implementations for abstract method tests.
- Improved test cases for handling timeouts and remote handler tracking in `test_timeout_handling.py` and `test_peer_remote_handlers.py`.
- Implement tests for HandlerDispatcher in `tests_v4/test_handler_dispatcher.py`, covering initialization, invocation, cancellation, argument building, result consumption, error handling, and handler execution.
- Introduce tests for Plugin loading functionalities in `tests_v4/test_loader.py`, including plugin specification, discovery, environment management, and loading components and handlers.
