feat(lighting): Phase G.2 — Setup.Lights + SetLightHook wiring

Register dat-defined LightInfos as runtime LightSources when entities
stream in. Every Setup (0x02xxxxxx) with a non-empty Lights dictionary
gets its per-part lights pulled via LightInfoLoader, which converts
the local Frame + ColorARGB + Intensity + Falloff + ConeAngle fields
into world-space LightSource records owned by the entity id.

Wire the LightingHookSink into the animation-hook router so retail's
SetLightHook animations (ignite-torch, extinguish-lamp) flip the
matching LightSource.IsLit latches. One hook may own multiple lights
(lamp-posts with two LightInfo entries) — the sink maintains an
owner-indexed map so all get toggled together.

Unregister on landblock unload: the streaming controller's
removeTerrain callback grabs the loaded landblock's entity list (new
GpuWorldState.TryGetLandblock helper) and drops every owner from the
sink before the entities disappear — otherwise walking across
landblocks accumulates stale LightSources.

9 new tests (LightingHookSink routing + LightInfoLoader conversion).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/AcDream.Core/Lighting/LightingHookSink.cs

@@ -0,0 +1,78 @@
+using System.Collections.Generic;
+using System.Numerics;
+using AcDream.Core.Physics;
+using DatReaderWriter.Types;
+
+namespace AcDream.Core.Lighting;
+
+/// <summary>
+/// Routes <see cref="SetLightHook"/> animation hooks to the
+/// <see cref="LightManager"/> — when a torch lights / extinguishes via
+/// an animation frame, flip the corresponding
+/// <see cref="LightSource.IsLit"/> latch. Per r13 §2 the hook is AC's
+/// way of saying "this Setup's baked-in LightInfo is now active".
+///
+/// <para>
+/// Registration: at entity spawn time the caller walks the Setup's
+/// <c>Lights</c> dictionary and registers a <see cref="LightSource"/>
+/// per <c>LightInfo</c>, tagging it with the owning entity id. When a
+/// hook fires later, we look up every light tagged to that owner and
+/// flip them all together (retail's SetLightHook is a per-setup
+/// boolean, not per-light).
+/// </para>
+/// </summary>
+public sealed class LightingHookSink : IAnimationHookSink
+{
+    private readonly LightManager _lights;
+
+    // Index owner → the set of LightSource instances they registered.
+    // Maintained lazily — populated on first RegisterLight for that owner.
+    private readonly Dictionary<uint, List<LightSource>> _byOwner = new();
+
+    public LightingHookSink(LightManager lights)
+    {
+        _lights = lights ?? throw new System.ArgumentNullException(nameof(lights));
+    }
+
+    /// <summary>
+    /// Register a light with the manager + track it by owner so later
+    /// SetLightHook / Unregister calls can reach it.
+    /// </summary>
+    public void RegisterOwnedLight(LightSource light)
+    {
+        System.ArgumentNullException.ThrowIfNull(light);
+        _lights.Register(light);
+        if (!_byOwner.TryGetValue(light.OwnerId, out var list))
+        {
+            list = new List<LightSource>();
+            _byOwner[light.OwnerId] = list;
+        }
+        list.Add(light);
+    }
+
+    /// <summary>Drop every light tagged to this owner (despawn / unload).</summary>
+    public void UnregisterOwner(uint ownerId)
+    {
+        if (!_byOwner.TryGetValue(ownerId, out var list)) return;
+        foreach (var l in list) _lights.Unregister(l);
+        _byOwner.Remove(ownerId);
+    }
+
+    /// <summary>
+    /// Get the set of registered lights for an owner — exposed so
+    /// callers can reposition them (torch on hand follows hand part).
+    /// </summary>
+    public IReadOnlyList<LightSource>? GetOwnedLights(uint ownerId)
+    {
+        return _byOwner.TryGetValue(ownerId, out var list) ? list : null;
+    }
+
+    public void OnHook(uint entityId, Vector3 entityWorldPosition, AnimationHook hook)
+    {
+        if (hook is not SetLightHook slh) return;
+        if (!_byOwner.TryGetValue(entityId, out var list)) return;
+
+        foreach (var light in list)
+            light.IsLit = slh.LightsOn;
+    }
+}