refactor(battle-node): extract InitBattleHandler

SVSim.BattleNode/Sessions/BattleSession.cs

@@ -37,6 +37,7 @@ public sealed class BattleSession
         new Dictionary<NetworkBattleUri, IFrameHandler>
         {
             [NetworkBattleUri.InitNetwork] = new InitNetworkHandler(),
+            [NetworkBattleUri.InitBattle] = new InitBattleHandler(),
         };
 
     private FrameDispatchContext BuildContext(IBattleParticipant from, MsgEnvelope env) =>

SVSim.BattleNode/Sessions/Dispatch/Handlers/InitBattleHandler.cs

@@ -0,0 +1,36 @@
+using SVSim.BattleNode.Lifecycle;
+using SVSim.BattleNode.Protocol;
+
+namespace SVSim.BattleNode.Sessions.Dispatch.Handlers;
+
+internal sealed class InitBattleHandler : IFrameHandler
+{
+    public IReadOnlyList<DispatchRoute> Handle(FrameDispatchContext ctx)
+    {
+        // case 2: Bot — ack only, NO Matched (Matched would corrupt client opponent info).
+        if (ctx.Type == BattleType.Bot && ctx.SenderPhase == BattleSessionPhase.AwaitingInitBattle)
+        {
+            var r = new List<DispatchRoute>
+            {
+                new(ctx.From, BattleFrames.BuildAck(NetworkBattleUri.InitBattle), true),
+            };
+            ctx.SenderPhase = BattleSessionPhase.AwaitingLoaded;
+            return r;
+        }
+
+        // case 5: general — push Matched (per-perspective) to the sender only.
+        if (ctx.SenderPhase == BattleSessionPhase.AwaitingInitBattle)
+        {
+            var r = new List<DispatchRoute>
+            {
+                new(ctx.From, ScriptedLifecycle.BuildMatched(
+                    ctx.From.Context, ctx.Other.Context, ctx.From.ViewerId, ctx.Other.ViewerId,
+                    ctx.BattleId, ScriptedProfiles.BattleSeed), false),
+            };
+            ctx.SenderPhase = BattleSessionPhase.AwaitingLoaded;
+            return r;
+        }
+
+        return Array.Empty<DispatchRoute>();
+    }
+}