feat: add SendTo to Hub interface for direct WS message delivery

Expose SendTo on the public Hub interface so gameserver steps can
deliver messages directly to a connection by connectionId, without
requiring the connection to be in a named room.

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

Author: intel352

internal/hub.go

@@ -157,6 +157,12 @@ func (h *hub) broadcastToRoom(room string, msg []byte, exclude string) {
 	}
 }
 
+// SendTo delivers msg directly to a connection by connID.
+// Returns true if the message was queued. Satisfies the gameserver plugin's ws_bridge.WSHub interface.
+func (h *hub) SendTo(connID string, msg []byte) bool {
+	return h.sendTo(connID, msg)
+}
+
 // JoinRoom adds connID to the named room. Returns true if the connection was registered.
 // This satisfies the gameserver plugin's ws_bridge.WSHub interface.
 func (h *hub) JoinRoom(connID, room string) bool {

plugin.go

@@ -15,6 +15,8 @@ func NewWebSocketPlugin() sdk.PluginProvider {
 // Satisfied by the internal hub after the ws.server module is initialized.
 type Hub interface {
 	BroadcastToRoom(room string, msg []byte) int
+	// SendTo delivers a message directly to a connection by its ID.
+	SendTo(connID string, msg []byte) bool
 }
 
 // GetHub returns the global WebSocket hub once the ws.server module has been