feat(quest): QT6 — plugins can read the contract tracker

The last piece of QT6's own scope: r10-quest-dialogs.md §11.6's contract half.
IGameState.Contracts exposes what the client structurally knows about quests,
which — per that same research — is the tracker and nothing else. The rest of
§11.6 (chat stream, tells, give, use, confirmations) is other features and
stays out of this campaign.

A pull-through source rather than a pushed mirror. Contracts change rarely and
are already owned canonically, so a second copy would only be a thing to keep
in step; reading through means a plugin cannot observe a stale list.

Both hosts implement it. The headless one carries contract id, stage and
progress but no names — a bot has no dat access — because losing the TEXT is
expected while losing the QUEST would leave a bot silently unable to see what
it is on. Same rule covers a contract the installed dat has never heard of: it
still projects, with empty text and a correct status, rather than vanishing.

The interface member is defaulted so a host predating this campaign still
satisfies IGameState.

Two lazy catalog loads exist (the panel's and this one) rather than one shared
instance. That is deliberate: threading a shared ContractCatalog through three
composition records to avoid reading a 322-row immutable table at most twice
per session would be plumbing for no correctness or performance gain, and the
comment at the call site says so.

Campaign QT is complete; the connected user gate is owed.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/AcDream.App/Composition/SessionPlayerComposition.cs

@@ -278,6 +278,30 @@ internal sealed class SessionPlayerCompositionPhase
             d.DatLock,
             world.TerrainBuild.HeightTable,
             d.Options.DumpSceneryZ);
+        // Campaign QT slice QT6: the plugin-facing contract view. A
+        // pull-through source rather than a mirror, so a plugin always reads
+        // the canonical tracker instead of a copy that could fall behind it.
+        //
+        // The catalog is loaded lazily and independently of the Journal
+        // panel's own. Two reads of a 322-row immutable table across a whole
+        // session is not worth threading a shared instance through three
+        // composition records for; correctness is identical either way.
+        AcDream.Core.Quests.ContractCatalog? pluginContractCatalog = null;
+        d.WorldGameState.ContractsSource = () =>
+        {
+            if (pluginContractCatalog is null)
+            {
+                lock (d.DatLock)
+                    pluginContractCatalog =
+                        AcDream.Content.ContractTableReader.Load(content.Dats);
+            }
+
+            return AcDream.Runtime.Gameplay.ContractPluginProjection.Project(
+                d.Runtime.ContractsOwner.View,
+                pluginContractCatalog,
+                DateTime.UtcNow);
+        };
+
         var streamerLease = scope.Acquire(
             "landblock streamer",
             () => LandblockStreamer.CreateForRequests(

src/AcDream.Core/Plugins/WorldGameState.cs

@@ -10,6 +10,19 @@ public sealed class WorldGameState : IGameState
 
     public IReadOnlyList<WorldEntitySnapshot> Entities => _entities;
 
+    /// <summary>
+    /// Where <see cref="Contracts"/> reads from. Set once by the host.
+    /// </summary>
+    /// <remarks>
+    /// A pull-through source rather than a pushed list: contracts change rarely
+    /// and are already owned canonically elsewhere, so mirroring them here
+    /// would add a second copy to keep in step for no gain.
+    /// </remarks>
+    public Func<IReadOnlyList<ContractSnapshot>>? ContractsSource { get; set; }
+
+    public IReadOnlyList<ContractSnapshot> Contracts =>
+        ContractsSource?.Invoke() ?? [];
+
     /// <summary>
     /// Publish the current projection for an entity. Re-hydration replaces the
     /// prior snapshot instead of turning the current-state API into history.

src/AcDream.Headless/Plugins/HeadlessPluginHost.cs

@@ -99,6 +99,25 @@ internal sealed class HeadlessPluginHost
         }
     }
 
+    /// <summary>
+    /// Campaign QT slice QT6. Same borrow-don't-own shape as
+    /// <see cref="Entities"/>: projected from the canonical tracker on read.
+    /// Names and status text are empty here — a headless host has no dat
+    /// access — while every numeric field a bot actually branches on
+    /// (contract id, stage, progress) is present.
+    /// </summary>
+    public IReadOnlyList<ContractSnapshot> Contracts
+    {
+        get
+        {
+            ObjectDisposedException.ThrowIf(_disposed, this);
+            return AcDream.Runtime.Gameplay.ContractPluginProjection.Project(
+                _runtime.ContractsOwner.View,
+                catalog: null,
+                now: DateTime.UtcNow);
+        }
+    }
+
     public event Action<WorldEntitySnapshot> EntitySpawned
     {
         add

src/AcDream.Plugin.Abstractions/ContractSnapshot.cs

@@ -0,0 +1,41 @@
+namespace AcDream.Plugin.Abstractions;
+
+/// <summary>
+/// One tracked contract, as a plugin sees it.
+/// </summary>
+/// <remarks>
+/// <para>
+/// This is the ONLY structured view of quest state a client ever has. The
+/// retail client stores no quest flags and is never told one changed; it learns
+/// about quests through NPC dialogue, generic error text, and this tracker. A
+/// plugin asking "what quests am I on?" is asking this and nothing else.
+/// </para>
+/// <para>
+/// <paramref name="Name"/>, <paramref name="Description"/> and
+/// <paramref name="Status"/> come from the installed dat and may be empty on a
+/// host with no dat access (a headless bot), or for a contract the installed
+/// dat build has never heard of. The numeric fields are always present.
+/// </para>
+/// </remarks>
+/// <param name="ContractId">Key into the dat's ContractTable.</param>
+/// <param name="Stage">
+/// Raw wire stage: 1 available, 2 in progress, 3 done-or-pending-repeat, and
+/// <c>4 + n</c> for a progress counter with n steps done — see
+/// <paramref name="Progress"/>.
+/// </param>
+/// <param name="Progress">Completed steps, or 0 when the stage carries no counter.</param>
+/// <param name="IsDisplayed">Whether the server nominated this as the shown contract.</param>
+/// <param name="Name">Authored contract name.</param>
+/// <param name="Description">Authored long-form description.</param>
+/// <param name="Status">
+/// The progress text retail's own panel shows — "Available", "In Progress",
+/// "5/20 Tuskers", "Done (1h 30s to Repeat)".
+/// </param>
+public readonly record struct ContractSnapshot(
+    uint ContractId,
+    uint Stage,
+    uint Progress,
+    bool IsDisplayed,
+    string Name = "",
+    string Description = "",
+    string Status = "");

src/AcDream.Plugin.Abstractions/IGameState.cs

@@ -4,4 +4,15 @@ namespace AcDream.Plugin.Abstractions;
 public interface IGameState
 {
     IReadOnlyList<WorldEntitySnapshot> Entities { get; }
+
+    /// <summary>
+    /// The player's tracked contracts — the client's only structured view of
+    /// quest state (<c>r10-quest-dialogs.md</c> §1.3). Empty when the server
+    /// has sent none.
+    /// </summary>
+    /// <remarks>
+    /// Defaulted so a host predating Campaign QT still satisfies the interface;
+    /// both in-tree hosts implement it.
+    /// </remarks>
+    IReadOnlyList<ContractSnapshot> Contracts => [];
 }

src/AcDream.Runtime/Gameplay/ContractPluginProjection.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+using AcDream.Core.Net.Messages;
+using AcDream.Core.Quests;
+using AcDream.Plugin.Abstractions;
+
+namespace AcDream.Runtime.Gameplay;
+
+/// <summary>
+/// Projects the canonical contract tracker into the plugin-facing
+/// <see cref="ContractSnapshot"/> shape.
+/// </summary>
+/// <remarks>
+/// Lives here rather than in either host because both of them need it and
+/// neither owns the tracker. The authored catalog is optional: a headless bot
+/// has no dat access, and a contract the installed dat has never heard of still
+/// has to appear — a plugin must not silently miss a live quest because the
+/// text for it is unavailable.
+/// </remarks>
+public static class ContractPluginProjection
+{
+    public static IReadOnlyList<ContractSnapshot> Project(
+        IRuntimeContractView contracts,
+        ContractCatalog? catalog,
+        DateTime now)
+    {
+        ArgumentNullException.ThrowIfNull(contracts);
+
+        IReadOnlyList<ContractTracker> tracked = contracts.GetContracts();
+        if (tracked.Count == 0)
+            return [];
+
+        uint displayed = contracts.Snapshot.DisplayContractId;
+        var result = new ContractSnapshot[tracked.Count];
+        for (int i = 0; i < tracked.Count; i++)
+        {
+            ContractTracker tracker = tracked[i];
+            ContractEntry? entry = catalog?.Lookup(tracker.ContractId);
+
+            result[i] = new ContractSnapshot(
+                tracker.ContractId,
+                (uint)tracker.Stage,
+                tracker.Progress,
+                tracker.ContractId == displayed,
+                entry?.ContractName ?? string.Empty,
+                entry?.Description ?? string.Empty,
+                entry is null
+                    ? string.Empty
+                    : ContractProgressText.Build(
+                        (uint)tracker.Stage,
+                        tracker.TimeWhenRepeats,
+                        tracker.ReceivedAt,
+                        entry,
+                        now));
+        }
+
+        return result;
+    }
+}