Import march-2020-03-10 from private repo (scrubbed 2026-05-27)

Targets Rec Room 2020.03.10 client (also serves 2020.03.06).

Re-import after adding:
- DorkNet.ClientMod/dorknet-clientmod.json.template — config schema
  the launcher's manifest-driven patcher renders into UserData/.
- tools/build-patcher-zip.ps1 — produces dorknet-clientpatch-{key}.zip
  for v1-march-* Release uploads.
- .github/workflows/release.yml — on tag push publishes both
  dorknet-server-march_2020_03_10-win-x64.zip and
  dorknet-clientpatch-march_2020_03_10.zip as Release assets.

Same scrub rules as december; tools/build-patcher-zip.ps1 added to
the maintainer-side allow-list so it survives.

DorkNet.Server/Data/Entities/RoomSceneEntity.cs

@@ -0,0 +1,60 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace DorkNet.Server.Data.Entities;
+
+/// <summary>
+/// One scene within a multi-scene custom room. Most rooms historically
+/// had only Scenes[0] (synthesised in <c>BuildRoomDetails</c> from
+/// <see cref="RoomEntity.LocationReplicationId"/> +
+/// <see cref="RoomEntity.CurrentDataBlobName"/>); rooms imported from a
+/// multi-scene archive write one row per chapter here, and the wire-shape
+/// builder emits the full <c>Scenes[]</c> array from this table when any
+/// rows exist.
+///
+/// <para>The scene's <see cref="RoomSceneId"/> on the wire is this table's
+/// <see cref="OrderIndex"/> — the matchmaking <c>SubRoomId</c> the watch
+/// passes to <c>/goto/room/{name}/{subroom}</c> matches against
+/// <see cref="Name"/>, then resolves to <see cref="OrderIndex"/> for
+/// <c>RoomInstance.SubRoomId</c>.</para>
+/// </summary>
+public class RoomSceneEntity
+{
+    public long Id { get; set; }
+
+    /// <summary>FK to <see cref="RoomEntity"/>. Indexed so the per-room
+    /// fetch in <c>BuildRoomDetails</c> is one query.</summary>
+    public long RoomId { get; set; }
+
+    /// <summary>0-based index this scene occupies in the wire
+    /// <c>Scenes[]</c> array. Doubles as the <c>RoomSceneId</c> the
+    /// matchmaking flow uses for <c>RoomInstance.SubRoomId</c>.</summary>
+    public int OrderIndex { get; set; }
+
+    /// <summary>Display name (e.g. "Lobby", "Ch1_Headfirst"). Matched
+    /// case-insensitively against the sub-room segment of
+    /// <c>/goto/room/{name}/{subroom}</c>.</summary>
+    [MaxLength(128)]
+    public string Name { get; set; } = string.Empty;
+
+    /// <summary>The <c>RoomSceneLocationId</c> GUID the client uses to
+    /// look up the bundled stage prefab via
+    /// <c>AGRoomSettings.TryGetRoomSceneLocationById</c>. Defaults to
+    /// the MakerRoom (Basement) scene GUID — the canonical "blank
+    /// canvas" stage 2020 custom rooms were built on. Extracted from
+    /// resources.assets via tools/extract-locations-binary.py: the
+    /// "Maker Room" Location entry has SceneName=Basement and
+    /// ReplicationId=a75f7547-79eb-47c6-8986-6767abcb4f92.</summary>
+    [MaxLength(64)]
+    public string RoomSceneLocationId { get; set; } = "a75f7547-79eb-47c6-8986-6767abcb4f92";
+
+    /// <summary>The <see cref="RoomDataBlobEntity.BlobName"/> the watch
+    /// downloads as the persisted state for this scene.</summary>
+    [MaxLength(128)]
+    public string DataBlobName { get; set; } = string.Empty;
+
+    public int MaxPlayers { get; set; } = 8;
+    public bool IsSandbox { get; set; } = false;
+    public bool CanMatchmakeInto { get; set; } = true;
+
+    public DateTime DataModifiedAt { get; set; } = DateTime.UtcNow;
+}