feat: add editing and MCP command handling, enhance SSE streaming with usage tracking

- Implemented `Edit` and `McpAdd` commands in the command parser and handler.
- Added a new `stream` module to the runtime for handling streaming events.
- Enhanced `SseParser` to parse usage information from SSE events.
- Introduced `ToolCallAccumulator` for tracking tool calls independently.
- Updated `AppStateRest` to include `app_config` and `MiscState` to track `effort_level` and `selected_index`.
- Modified `LlmClient` to support streaming responses with usage tracking.
- Improved error handling and retry logic in the streaming API calls.
- Added tests for new features and improved markdown rendering in the chat view.

src/app/runtime/commands.rs

@@ -43,6 +43,12 @@ pub fn apply_command(command: Command) -> Vec<Action> {
         Command::Login { provider } => {
             vec![Action::StartOAuth { provider }]
         }
+        Command::Edit(path) => {
+            vec![Action::OpenEditor { path }]
+        }
+        Command::McpAdd { name, command } => {
+            vec![Action::McpAdd { name, command }]
+        }
         Command::Unknown(cmd) => {
             vec![Action::SystemNote {
                 kind: "error".to_string(),