ci: add ENet integration coverage

Game/tests/clock_smoke.gd

@@ -22,6 +22,10 @@ extends Node
 
 const PORT := 7801
 const RUN_SECONDS := 6.0
+# The client starts after the host, so its identical run window ends later.
+# Keep the host alive through that tail to avoid polling a deliberately
+# closed transport during a successful clock test.
+const HOST_GRACE_SECONDS := 1.0
 const CONVERGE_BY_SEC := 2.0
 const TICK_MS := 1000.0 / 60.0   # SimConstants.TICK_HZ, kept literal to avoid pulling in the whole project for one constant in a throwaway diagnostic
 const EPOCH_FILE := "/tmp/cosmicclash_clock_smoke_epoch_offset.txt"
@@ -89,6 +93,7 @@ func _on_clock_updated(rtt_ms: float, offset_ms: float) -> void:
 
 func _on_run_complete() -> void:
 	if _role != "client":
+		await get_tree().create_timer(HOST_GRACE_SECONDS).timeout
 		_finish(true, "host ran for %.1fs" % RUN_SECONDS)
 		return