10ms ws drain; ignore output_set

[sastraxi]

Extracted a new method poll_ws_messages() in handlers to process messages received by the WS thread. By doing so, we can call it more frequently and be more responsive to MOD-UI changes; now on the 10ms hot-loop.

Ignore output_set messages for performance reasons. These are sent frequently and we do not depend on them.

Branch stack

• 10ms ws drain; ignore output_set #166 (this branch)
  • Bypass source of truth is MOD-UI sastraxi/pi-stomp#34
    • Dual source-of-truth removed sastraxi/pi-stomp#35
      • Snapshot bypass via WS drain, drop per-plugin REST poll sastraxi/pi-stomp#37
        • Read bypass from the connect add dump sastraxi/pi-stomp#36

[sastraxi]

Already merged; included in #167