Add remote mesh commands to UI

Allow nodes to be rebooted, shut down, asked for their battery charge, put into programming mode, etc.

This can be through buttons in an admin screen or on the node details panel.

This feature can be limited to a group of administrators. We can also limit dangerous operations to unresponsive nodes.

These need to be implemented either using:
* protobuf commands enqueued to mqtt (for the gateway node to process)
* mqtt commands in a new json format that are processed by a new service running on the raspberry pi

stations have a "hardware node" field that is used with the --dest flag to meshtastic cli.

Start by locating the admin screen or node details panel and the handling of stations' "hardware node" field. Compare the two proposed command paths—protobuf messages enqueued to MQTT or a new JSON service on the Raspberry Pi—and review how the Meshtastic CLI uses the --dest flag. Done means the listed remote operations are available with the stated administrator and node-state restrictions.

Written by the indexing model from the issue text.