Fix DASP hostname resolution so localhost and hostnames work

The dispatch check compared the raw hostname string against the UDP
source IP, silently dropping responses when they differed (e.g.
"localhost" vs "127.0.0.1"). Resolve hostname to IP at session init.

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

dasp.py

@@ -589,7 +589,7 @@ class DaspSession:
     def __init__(self, dasp_socket, session_id, host, port, **options):
         self.socket = dasp_socket
         self.id = session_id
-        self.host = host
+        self.host = socket.gethostbyname(host)
         self.port = port
         self.remote_id = -1
         self.is_closed = False