feat: Implement UVM Dashboard with frontend and backend integration

- Added dashboard.js for frontend functionality, including VM management and system health monitoring.
- Created dashboard route to serve the dashboard HTML.
- Introduced diagnostics route for token-protected host diagnostics.
- Enhanced VMs router with bulk actions, VM log retrieval, and port management.
- Updated lifecycle service to read VM log tails with truncation handling.
- Integrated static file serving for dashboard assets in the FastAPI server.
- Redirect root URL to the dashboard for improved user experience.

uvm/routers/dashboard.py

@@ -0,0 +1,17 @@
+"""Dashboard frontend routes."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+from fastapi import APIRouter
+from fastapi.responses import HTMLResponse
+
+router = APIRouter()
+
+_DASHBOARD_HTML = Path(__file__).parent.parent / "dashboard" / "static" / "index.html"
+
+
+@router.get("", response_class=HTMLResponse)
+def get_dashboard() -> str:
+    return _DASHBOARD_HTML.read_text(encoding="utf-8")