fix(rm): force-emit ctrl every tick (static alwaysEmitFields)

Realized control position is constant in steady state, so delta compression
emitted it ~once and the Grafana "% Control" line went invisible. Exempt
`ctrl` from delta compression so the pump's movement always traces.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/nodeClass.js

@@ -11,6 +11,10 @@ class nodeClass extends BaseNodeAdapter {
   static commands = commands;
   static tickInterval = null;
   static statusInterval = 1000;
+  // Realized control position holds constant in steady state, so delta
+  // compression would emit it ~once and the Grafana "% Control" line goes
+  // invisible. Force it every tick so the pump's movement always traces.
+  static alwaysEmitFields = ['ctrl'];
 
   buildDomainConfig(uiConfig) {
     _rejectLegacyAssetFields(uiConfig);