feat: introduce Nest workspace for local Firecracker management

- Added a new server module for the Nest workspace, integrating with UVM's API.
- Updated project description to reflect the new Nest functionality.
- Created tests for the Nest server and CLI, ensuring proper functionality and error handling.
- Refactored existing UVM server code to separate Nest and UVM functionalities.
- Removed the old UVM dashboard assets package as it is now part of the Nest workspace.
- Enhanced error messages for clarity regarding server shutdown commands.

uvm/routers/exit.py

@@ -25,7 +25,7 @@ def exit_server(
     if server is None:
         raise HTTPException(
             status_code=status.HTTP_503_SERVICE_UNAVAILABLE,
-            detail="server shutdown is unavailable outside uvm --serve",
+            detail="server shutdown is unavailable outside nest --serve or uvm --serve",
         )
     background_tasks.add_task(_request_server_exit, server)
     return ServerExitResponse()