refactor: abstract bambu specific protocol to printer agent

src/slic3r/Utils/IPrinterAgent.hpp

@@ -107,6 +107,19 @@ public:
                                       bool is_core_xy, bool supports_mqtt_axis_control, int sequence_id, bool lan_mode)
     { return ORCA_NETWORK_ERR_CMD_NOT_SUPPORTED; }
 
+    /**
+     * Build a ready-to-use local (LAN) camera stream URL for this agent's protocol.
+     * Returns an empty string if the agent has no local camera stream support.
+     */
+    virtual std::string get_local_camera_url(std::string dev_ip, std::string username, std::string password)
+    { return {}; }
+
+    /**
+     * Default LAN account username for this agent's protocol, if it has a fixed one.
+     * Returns an empty string if the agent has no fixed default (e.g. caller must supply one).
+     */
+    virtual std::string default_lan_username() const { return {}; }
+
     /**
      * Establish a direct LAN connection to a printer.
      */