Add initial S.M.A.R.T. support

- Implement SmartManager for collecting SMART data from SATA and NVMe drives
- Add smartctl-based data collection with standby mode detection
- Support comprehensive SMART attributes parsing and storage
- Add hub API endpoint for fetching SMART data from agents
- Create SMART table UI with detailed disk information

Co-authored-by: geekifan <i@ifan.dev>

internal/hub/hub.go

@@ -256,6 +256,8 @@ func (h *Hub) registerApiRoutes(se *core.ServeEvent) error {
 	apiAuth.GET("/containers/logs", h.getContainerLogs)
 	// get container info
 	apiAuth.GET("/containers/info", h.getContainerInfo)
+	// get SMART data
+	apiAuth.GET("/smart", h.getSmartData)
 	return nil
 }
 
@@ -321,6 +323,24 @@ func (h *Hub) getContainerInfo(e *core.RequestEvent) error {
 	}, "info")
 }
 
+// getSmartData handles GET /api/beszel/smart requests
+func (h *Hub) getSmartData(e *core.RequestEvent) error {
+	systemID := e.Request.URL.Query().Get("system")
+	if systemID == "" {
+		return e.JSON(http.StatusBadRequest, map[string]string{"error": "system parameter is required"})
+	}
+	system, err := h.sm.GetSystem(systemID)
+	if err != nil {
+		return e.JSON(http.StatusNotFound, map[string]string{"error": "system not found"})
+	}
+	data, err := system.FetchSmartDataFromAgent()
+	if err != nil {
+		return e.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
+	}
+	e.Response.Header().Set("Cache-Control", "public, max-age=60")
+	return e.JSON(http.StatusOK, data)
+}
+
 // generates key pair if it doesn't exist and returns signer
 func (h *Hub) GetSSHKey(dataDir string) (ssh.Signer, error) {
 	if h.signer != nil {