Feature: Add "Disconnect" option to app's Wi-Fi selector

[mcous]

overview

As a user with a robot connected to Wi-Fi, I want to disconnect that robot from Wi-Fi because I've don't want other people on the network to be able to connect to the robot.

This ticket is for tracking the addition of a "Disconnect" option to the Wi-Fi select UI that exercises the disconnect endpoint added by #4847. It takes over part of the UI described in #2718

acceptance criteria

• User presented an option to "Disconnect from ${network}" in Wi-Fi select field
  • https://zpl.io/anY8n9Y
• After clicking that option, the user is given a confirmation modal prior to actually disconnecting
  • https://zpl.io/bA43g4O
• Clicking the currently connected network in the selector does nothing

implementation notes

• Blocked by API endpoint addition in Feature: API endpoint for disconnecting from Wi-Fi #4847
• Blocked by react-select unification refactor in Refactor: Create common react-select wrapper component #4844

#2718 describes functionality that disables the Wi-Fi selector when not currently connected to the robot via Ethernet. This functionality is out of scope for this ticket and will be addressed by a separate ticket