refactor(runtime): cut graphical host over to canonical root

Make every App composition phase borrow one GameRuntime, retire the duplicate view/event adapters, and dispose the root only after its graphical borrowers release. This preserves synchronous UI commands while giving shutdown one exact ownership ledger.

Co-authored-by: OpenAI Codex <codex@openai.com>

tests/AcDream.App.Tests/GameRuntimeTestFactory.cs

@@ -0,0 +1,62 @@
+using AcDream.Core.Combat;
+using AcDream.Core.Items;
+using AcDream.Core.Spells;
+using AcDream.Runtime;
+using AcDream.Runtime.Gameplay;
+using AcDream.Runtime.Session;
+
+namespace AcDream.App.Tests;
+
+internal static class GameRuntimeTestFactory
+{
+    public static GameRuntime Create(
+        IRuntimeCombatAttackOperations? combatAttack = null,
+        IRuntimeCombatTargetOperations? combatTarget = null,
+        IRuntimeCombatModeOperations? combatMode = null,
+        IRuntimeSpellCastOperations? spellCast = null,
+        ILiveSessionOperations? session = null,
+        Func<double>? combatTime = null)
+    {
+        var fallback = new NoopOperations();
+        return new GameRuntime(new GameRuntimeDependencies(
+            combatAttack ?? fallback,
+            combatTarget ?? fallback,
+            combatMode ?? fallback,
+            spellCast ?? fallback,
+            SessionOperations: session,
+            CombatTime: combatTime));
+    }
+
+    private sealed class NoopOperations :
+        IRuntimeCombatAttackOperations,
+        IRuntimeCombatTargetOperations,
+        IRuntimeCombatModeOperations,
+        IRuntimeSpellCastOperations
+    {
+        public bool CanStartAttack() => false;
+        public void PrepareAttackRequest() { }
+        public bool SendAttack(AttackHeight height, float power) => false;
+        public void SendCancelAttack() { }
+        public bool IsDualWield => false;
+        public bool PlayerReadyForAttack => false;
+        public bool AutoRepeatAttack => false;
+        public bool AutoTarget => false;
+        public uint? SelectClosestTarget() => null;
+        public bool IsInWorld => false;
+        public IReadOnlyList<ClientObject> GetOrderedEquipment() => [];
+        public void NotifyExplicitCombatModeRequest() { }
+        public void SendChangeCombatMode(CombatMode mode) { }
+        public uint LocalPlayerId => 0u;
+        public bool CanSend => false;
+        public bool HasRequiredComponents(uint spellId) => false;
+        public bool IsTargetCompatible(
+            uint targetId,
+            SpellMetadata spell,
+            bool showMessage) => false;
+        public void StopCompletely() { }
+        public void SendUntargeted(uint spellId) { }
+        public void SendTargeted(uint targetId, uint spellId) { }
+        public void DisplayMessage(string message) { }
+        public void IncrementBusy() { }
+    }
+}