[FEATURE]:Add refresh Folder Tree #30661

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Describe the enhancement you want to request

Feature Description

Currently, when a new file or folder is added to the workspace directly from the file system (or via external tools), the OpenCode Explorer/Folder Tree does not automatically detect and display the newly created items. Users have to manually close and reopen the workspace or restart the application to see the updates, which differs from the seamless real-time syncing behavior found in VS Code.

This feature requests adding a manual Refresh button/action to the Folder Tree, or implementing a file system watcher to automatically trigger a refresh when changes occur.

Expected Behavior

• Manual Trigger: A "Refresh" icon/button should be added to the Explorer/Folder Tree toolbar. Clicking it should force-reload the current directory structure.
• Context Menu: A "Refresh Explorer" option should be available in the right-click context menu of the workspace.
• (Optional but Ideal) Auto-Sync: Ideally, implement a file system watcher (like chokidar or native FS events) to automatically update the tree view when files are added, deleted, or renamed outside of OpenCode.

Current Behavior / Steps to Reproduce

1. Open a workspace folder in OpenCode.
2. Open your terminal or OS File Explorer, and create a new file inside that workspace directory (e.g., touch new-file.ts).
3. Look at the OpenCode Folder Tree -> The new-file.ts does not appear in the sidebar.
4. (Current workaround) There is no way to force a refresh other than reloading the entire workspace window.

Proposed Solution (Tech Stack Context)

• If handling manually: Add a click event to the Explorer toolbar that re-executes the file-tree fetching logic.
• If handling automatically: Leverage a file system watcher within the backend/node layer to dispatch an event to the frontend state (React/TypeScript) whenever a file-system mutation is detected.

Additional Context

• This feature will significantly improve DX (Developer Experience), especially when working with CLI code-generators or git checkouts that modify the file tree externally.
• Behavior reference: VS Code's built-in file watcher and its "Refresh Explorer" button.