Add auto-connect on Launch AR button press

Reads server host/port from start screen inputs and auto-connects
if not already connected when entering AR mode.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Main.gd

@@ -257,6 +257,19 @@ func _on_launch_ar_requested() -> void:
 	print("[Main] Launching AR mode")
 	current_phase = Phase.AR
 
+	# Auto-connect if not already connected
+	if not teleop_client.is_connected:
+		var host: String = start_screen.host_input.text.strip_edges()
+		var port: int = int(start_screen.port_input.text.strip_edges())
+		if host.is_empty():
+			host = "10.0.0.77"
+		if port <= 0 or port > 65535:
+			port = 8765
+		teleop_client.server_host = host
+		teleop_client.server_port = port
+		teleop_client.connect_to_server()
+		print("[Main] Auto-connecting to %s:%d" % [host, port])
+
 	# Enable passthrough
 	_enable_passthrough()