feat: improve chat streaming UX and add Mermaid diagram rendering (#438)

* feat: show current branch in empty chat state

* fix: display current git branch for worktrees and update them with branch change

* refactor: improve read tool output parsing with structured data

* feat: add support for message part delta events

* fix(chat): improve streaming rendering, scroll behavior, and assistant action visibility

* feat: Add mermaid diagram support to chat markdown rendering

* fix: update table download functionality to include success notification and remove unused MarkdownRenderer import

* refactor: streamline Streamdown component props for improved readability

* fix: preserve Streamdown code-block markers and use native Tauri cache clearing

* feat: add context overview panel to view conversation details

packages/web/server/index.js

@@ -3937,7 +3937,7 @@ function deriveSessionActivityTransitions(payload) {
     }
   }
 
-  if (payload.type === 'message.part.updated') {
+  if (payload.type === 'message.part.updated' || payload.type === 'message.part.delta') {
     const info = payload.properties?.info;
     const sessionId = info?.sessionID ?? info?.sessionId ?? payload.properties?.sessionID ?? payload.properties?.sessionId;
     const role = info?.role;
@@ -11177,7 +11177,6 @@ Context:
     res.json({ success: true, killedCount });
   });
 
-
   try {
     syncFromHmrState();
     if (await isOpenCodeProcessHealthy()) {