feat(battle-node): client-shaped handshake builders for the scripted bot

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

SVSim.BattleNode/Lifecycle/ScriptedLifecycle.cs

@@ -127,6 +127,37 @@ public static class ScriptedLifecycle
                 IdxChangeSeed: ScriptedProfiles.ReadyIdxChangeSeed,
                 Spin: ScriptedProfiles.ReadySpin));
 
+    // --- Client-shaped emissions used by ScriptedBotParticipant so the session brokers
+    // the bot through the same handshake arms as a human. Bodies for the parameterless
+    // handshake frames are ignored by the session (it reads from.Context / phase); only
+    // Swap's idxList is consumed (empty = keep the dealt hand).
+
+    public static MsgEnvelope BuildClientInitNetwork() => ClientFrame(NetworkBattleUri.InitNetwork, EmitCategory.General);
+    public static MsgEnvelope BuildClientInitBattle() => ClientFrame(NetworkBattleUri.InitBattle, EmitCategory.General);
+    public static MsgEnvelope BuildClientLoaded() => ClientFrame(NetworkBattleUri.Loaded, EmitCategory.General);
+
+    public static MsgEnvelope BuildClientSwap() =>
+        new(NetworkBattleUri.Swap,
+            ViewerId: FakeOpponentViewerId,
+            Uuid: WireConstants.ServerUuid,
+            Bid: null,
+            Try: 0,
+            Cat: EmitCategory.Battle,
+            PubSeq: null,
+            PlaySeq: null,
+            Body: new RawBody(new Dictionary<string, object?> { ["idxList"] = new List<object?>() }));
+
+    private static MsgEnvelope ClientFrame(NetworkBattleUri uri, EmitCategory cat) =>
+        new(uri,
+            ViewerId: FakeOpponentViewerId,
+            Uuid: WireConstants.ServerUuid,
+            Bid: null,
+            Try: 0,
+            Cat: cat,
+            PubSeq: null,
+            PlaySeq: null,
+            Body: new ResultCodeOnlyBody());
+
     /// <summary>
     /// First half of the v1.1 scripted opponent turn cycle: pushed after the player's
     /// TurnEnd, transitions the client into "Opponent's turn…" state. Paired with