Reset data channel seq every connect (closes #336) (#2431)

Reset inSequence back to 1 every time we connect to the Engine,
otherwise we'll continue to think the current sequence is a high number
(while the engine has no memory of the last session -- and may even be a
new engine instance!) and ignore messages until we pass that counter
again.

Signed-off-by: Paul Tagliamonte <paul@zoo.dev>

src/lang/std/engineConnection.ts

@@ -551,6 +551,7 @@ class EngineConnection {
           // Everything is now connected.
           this.state = { type: EngineConnectionStateType.ConnectionEstablished }
 
+          this.engineCommandManager.inSequence = 1
           this.onEngineConnectionOpen(this)
         })