fix(battle-node): node_server_url matches prod wire format (no scheme, with path)

Prod do_matching captures (data_dumps/captures/traffic_prod_tk2_*) send
the node URL as host:port/socket.io/ with no scheme prefix —
e.g. "node06.shadowverse.jp:13560/socket.io/". BestHTTP's SocketManager
expects this exact shape; the leading ws:// we were sending plus the
missing /socket.io/ path was preventing the client from completing the
post-do_matching connect (eventually times out with "connection timed
out").

Update BattleNodeOptions default, Program.cs override, and both
controller and bridge tests to use "localhost:5148/socket.io/".

Discovered during v1 smoke walkthrough.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.BattleNode/Bridge/BattleNodeOptions.cs

@@ -1,10 +1,11 @@
 namespace SVSim.BattleNode.Bridge;
 
 /// <summary>
-/// DI-injected options for the battle node. The web host populates these — typically
-/// nodeServerUrl is "ws://localhost:5148" matching ASPNETCORE_URLS.
+/// DI-injected options for the battle node. NodeServerUrl matches the prod
+/// do_matching wire format: <c>host:port/socket.io/</c>, no scheme prefix.
+/// BestHTTP's SocketManager parses it as the Socket.IO v2 endpoint URL.
 /// </summary>
 public sealed class BattleNodeOptions
 {
-    public string NodeServerUrl { get; set; } = "ws://localhost:5148";
+    public string NodeServerUrl { get; set; } = "localhost:5148/socket.io/";
 }