fix: trade gate round 2 - the trade window is state-managed, never

layout-persisted; deeper [trade] wire probes

A session that ended mid-trade saved Visible=true for "secure-trade" in
the window-layout file, restoring an empty open trade window at every
launch. Added to the stateManagedVisibilityWindows set beside
Combat/JumpPowerbar/ExternalContainer/Vendor - visibility belongs to
RuntimeTradeState's open/closed lifecycle exclusively.

Also carries the round-2 [trade] probes for the still-open "open never
registers" diagnosis: the round-1 log proved the request seam fires
(4x "request partner=0x50000001 item=0 open=False") but no window ever
opened - the new probes bracket the command router (open-cmd sent
flag), the wire send (wire-open seq), and the inbound RegisterTrade
apply, so the next gate log pinpoints whether the send leaves the
client and whether ACE replies.

App suite 4,990/3 skips.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/AcDream.Core.Net/WorldSession.cs

@@ -2568,6 +2568,8 @@ public sealed class WorldSession : IDisposable
     public void SendOpenTradeNegotiations(uint partnerGuid)
     {
         uint seq = NextGameActionSequence();
+        // TEMPORARY [trade] probe (2026-08-14 gate round 2).
+        Console.WriteLine($"[trade] wire-open partner=0x{partnerGuid:X8} seq={seq}");
         SendGameAction(TradeRequests.BuildOpenTradeNegotiations(seq, partnerGuid));
     }