refactor(rpc, runtime, track): Improve documentation and error handling across core modules

- Overhauled code comments in `rpc.rs` to clarify handler roles, fallback strategies, and VS Code RPC contract alignment
- Standardized error reporting using `error_utils` with specific error codes (e.g. "EBADARG_DIALOG_OPTS") throughout RPC methods
- Renamed helpers like `path_to_uri_components_value` to `file_path_to_uri_components_dto` with improved error logging
- Enhanced `AppRuntime` documentation in `runtime.rs` to emphasize effect execution flow and environment integration
- Refined Track dispatcher logic to use consistent JSON-RPC error formatting and parameter validation helpers
- Added detailed method documentation for terminal operations, status bar updates, and filesystem API handlers
- Implemented type-safe parameter extraction in RPC handlers with contextual error messages
- Unified effect creation patterns in Track for language feature registration and configuration management

Impact: Strengthens foundation for extension host communication, improves debugability through structured errors, and ensures better alignment with VS Code's extension protocol requirements.

Author: NikolaRHristov