[Bafy78]

Fixes #19.

DummyClientConnection has no channel, so Connection.isConnected() is always false and vanilla's send(packet, listener, flush), flushChannel() and runOnceConnected() add their work to pendingActions, waiting for a channel that never comes. Every packet addressed to a dummy was kept alive for the dummy's whole lifetime.

This overrides the three methods as no-ops. The one- and two-argument send overloads delegate to the three-argument one, so this covers every outbound path. Packet callbacks never ran before either (the queue was never flushed), so the only observable change is the memory.

Testing

Minecraft 26.3, Fabric API 0.161.0+26.3, dedicated server, 3 GB heap, flat world, 300 armor stands teleported every tick by a repeating command block, 20 dummies; heap measured with jcmd GC.run + GC.heap_info, baseline with no dummy 221–224 MB:

post-full-GC heap	dummies just spawned	30 s later
2.7.0	302 MB	368 MB, still climbing
this PR	288 MB	292 MB

Dummies still spawn, walk, respawn and leave. Departed dummies are still retained after dummy leave because of #20; that is fixed separately in the follow-up PR (with both, the heap returns to baseline once the dummies have left).