feat(battle-node): Bot dispatch arms in ComputeFrames

Three new arms gated on Type == BattleType.Bot, placed before the
existing PvP / Scripted arms:
- InitBattle → ack to sender (no Matched push — client uses AIBattleStart HTTP data)
- Loaded → silent (no BattleStart, no Deal — client short-circuits to GotoBattle)
- TurnEnd / TurnEndFinal → Judge to sender only (not broadcast)

Other URIs in Bot mode fall through existing arms: Swap is Type-agnostic
(per-sender SwapResponse + Ready), Retire/Kill hits the existing
Scripted no-contest BattleFinish(Win), gameplay forwarders are gated on
Pvp so Bot's PlayActions/Echo/etc. fall through default (drop). 8 new
dispatch tests cover the wire contract.

Reference: docs/api-spec/in-battle/ai-passive.md.

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

SVSim.UnitTests/BattleNode/Sessions/BattleSessionDispatchTests.cs

@@ -431,6 +431,140 @@ public class BattleSessionDispatchTests
         Assert.That(((BattleFinishBody)routes[0].Frame.Body).Result, Is.EqualTo(BattleResult.Win));
     }
 
+    private static (BattleSession, FakeRealParticipant, FakeParticipant) NewBotSession()
+    {
+        var a = new FakeRealParticipant(viewerId: 1001, PlayerACtx());
+        var b = new FakeParticipant(viewerId: ScriptedLifecycle.FakeOpponentViewerId, NoOpBotContext());
+        var s = new BattleSession("bid-bot-1", BattleType.Bot, a, b, NullLogger<BattleSession>.Instance);
+        return (s, a, b);
+    }
+
+    private static MatchContext NoOpBotContext() => new(
+        SelfDeckCardIds: Array.Empty<long>(),
+        ClassId: "0", CharaId: "0", CardMasterName: "card_master_node_10015",
+        CountryCode: "", UserName: "Bot", SleeveId: "0",
+        EmblemId: "0", DegreeId: "0", FieldId: 0, IsOfficial: 0, BattleType: 0);
+
+    [Test]
+    public void Bot_InitNetwork_acks_to_sender()
+    {
+        var (s, a, _) = NewBotSession();
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+
+        Assert.That(routes.Count, Is.EqualTo(1));
+        Assert.That(routes[0].Target, Is.SameAs(a));
+        Assert.That(routes[0].Frame.Uri, Is.EqualTo(NetworkBattleUri.InitNetwork));
+        Assert.That(a.Phase, Is.EqualTo(BattleSessionPhase.AwaitingInitBattle));
+    }
+
+    [Test]
+    public void Bot_InitBattle_acks_to_sender_with_no_Matched_push()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+
+        Assert.That(routes.Count, Is.EqualTo(1), "Bot InitBattle is ack-only, no Matched push.");
+        Assert.That(routes[0].Target, Is.SameAs(a));
+        Assert.That(routes[0].Frame.Uri, Is.EqualTo(NetworkBattleUri.InitBattle),
+            "Expected an ack envelope for InitBattle, NOT a Matched envelope.");
+        Assert.That(a.Phase, Is.EqualTo(BattleSessionPhase.AwaitingLoaded));
+    }
+
+    [Test]
+    public void Bot_Loaded_produces_no_routes_but_advances_phase()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+
+        Assert.That(routes, Is.Empty, "Bot Loaded is silent.");
+        Assert.That(a.Phase, Is.EqualTo(BattleSessionPhase.AwaitingSwap),
+            "Phase still advances even though there are no outbound routes.");
+    }
+
+    [Test]
+    public void Bot_Swap_per_sender_SwapResponse_plus_Ready()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Swap));
+
+        Assert.That(routes.Select(r => r.Frame.Uri),
+            Is.EqualTo(new[] { NetworkBattleUri.Swap, NetworkBattleUri.Ready }));
+        Assert.That(routes.All(r => ReferenceEquals(r.Target, a)), Is.True);
+        Assert.That(a.Phase, Is.EqualTo(BattleSessionPhase.AfterReady));
+    }
+
+    [Test]
+    public void Bot_TurnEnd_pushes_Judge_to_sender_only()
+    {
+        var (s, a, b) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Swap));
+
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.TurnEnd));
+
+        Assert.That(routes.Count, Is.EqualTo(1), "Bot TurnEnd → exactly one Judge frame back.");
+        Assert.That(routes[0].Target, Is.SameAs(a), "Judge target is the sender, not broadcast.");
+        Assert.That(routes[0].Frame.Uri, Is.EqualTo(NetworkBattleUri.Judge));
+    }
+
+    [Test]
+    public void Bot_TurnEndFinal_pushes_Judge_to_sender_only()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Swap));
+
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.TurnEndFinal));
+
+        Assert.That(routes.Count, Is.EqualTo(1));
+        Assert.That(routes[0].Frame.Uri, Is.EqualTo(NetworkBattleUri.Judge));
+        Assert.That(routes[0].Target, Is.SameAs(a));
+    }
+
+    [Test]
+    public void Bot_PlayActions_drops_no_recipient()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Swap));
+
+        // Bot's PlayActions falls through the default arm — the Pvp forwarder is gated
+        // on Type == Pvp, so Bot's gameplay frames have no routing rule and drop.
+        // (The PvP semantics would have been "forward to NoOp which swallows" — same
+        // observable result, but cleaner to leave them as default-drops.)
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.PlayActions));
+
+        Assert.That(routes, Is.Empty);
+    }
+
+    [Test]
+    public void Bot_Retire_pushes_BattleFinish_Win_to_sender()
+    {
+        var (s, a, _) = NewBotSession();
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitNetwork));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.InitBattle));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Loaded));
+        s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Swap));
+
+        var routes = s.ComputeFrames(a, NewEnvelope(NetworkBattleUri.Retire));
+
+        Assert.That(routes.Count, Is.EqualTo(1));
+        Assert.That(routes[0].Target, Is.SameAs(a));
+        Assert.That(routes[0].Frame.Uri, Is.EqualTo(NetworkBattleUri.BattleFinish));
+    }
+
     private static (BattleSession, FakeRealParticipant, FakeRealParticipant) NewPvpSession()
     {
         var a = new FakeRealParticipant(viewerId: 1001, PlayerACtx());