When the start button is pressed, switch to a "connecting" state. This
triggers the spawning of the "connecting" UI message and the connection
startup.
When the connection task finishes, `fn handle_tasks()` collects it and
pushes the CommandQueue into the main world just as before. In addition,
it will change to the "playing" state, which triggers the despawning of
the UI notice.
There is no meaningful connection-error handling path. A failed
connection will print a warning to stdout, and that is all.
There is still no transmitter at all, nor is the receiver hooked up to
one of the paddles.
Robert Garrett
7837ab49b0