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/state/rest.rs

@@ -8,6 +8,7 @@ use super::runtime::{SessionRuntime, TurnEvent};
 use super::types::{AgentMode, Origin, Toast, TranscriptCache};
 use crate::app::mcp::manager::McpManager;
 use crate::app::workflow::engine::WorkflowEngine;
+use crate::model::app_config::AppConfig;
 use crate::model::editlog::EditLog;
 use crate::model::settings::Settings;
 
@@ -32,6 +33,7 @@ impl ChatMessageDisplay {
 pub struct AppStateRest {
     pub mode: AgentMode,
     pub settings: Settings,
+    pub app_config: AppConfig,
     pub workspace_roots: Vec<PathBuf>,
     pub session_id: String,
     pub session_dir: PathBuf,
@@ -57,6 +59,7 @@ pub struct AppStateRest {
 impl AppStateRest {
     pub fn new(workspace_roots: Vec<PathBuf>, session_dir: PathBuf, memory_dir: PathBuf) -> Self {
         let settings = Settings::load();
+        let app_config = AppConfig::load();
         let download_dir = memory_dir.parent().unwrap_or(&memory_dir).join("downloads");
         let worktrees_dir = memory_dir.parent().unwrap_or(&memory_dir).join("worktrees");
         let dir_cache = DirCache::new();
@@ -67,6 +70,7 @@ impl AppStateRest {
         AppStateRest {
             mode: AgentMode::Normal,
             settings,
+            app_config,
             workspace_roots,
             session_id,
             session_dir: session_dir.clone(),