feat: Настройки › Автообновление - clients compare their version with the server's every N and update themselves; the server looks at GitLab every N and, when a newer release is out, offers it to an administrator at login (after the PIN) with «Обновить» and «Отказаться»; the words of a made picture's result are the model's only

internal/proto/proto.go

@@ -103,8 +103,19 @@ type WSMsg struct {
 	Transport string          `json:"transport,omitempty"`
 	Fallback  string          `json:"fallback,omitempty"`
 	Main      string          `json:"main,omitempty"`
+	// Auto-update of agents: how often (minutes) an agent compares its
+	// version with the server's and updates itself if the server's is newer;
+	// 0 or missing - it does not. ServerVersion is the server's.
+	AutoUpdate    int    `json:"autoupdate,omitempty"`
+	ServerVersion string `json:"server_version,omitempty"`
 }
 
+// Headers with the same on the poll answer and on /api/agent/config.
+const (
+	AutoUpdateHeader    = "X-Auto-Update"    // minutes, "0" or missing: off
+	ServerVersionHeader = "X-Server-Version" // the server's release version
+)
+
 // Terminal / stream frame types on the session "in" channel (server -> agent).
 // Reused for both PTY terminals and raw TCP port-forward streams.
 const (