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/Migrations/20260508170534_Phase14Subscriptions.cs

@@ -0,0 +1,53 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace DorkNet.Server.Migrations
+{
+    /// <inheritdoc />
+    public partial class Phase14Subscriptions : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Subscriptions",
+                columns: table => new
+                {
+                    Id = table.Column<long>(type: "INTEGER", nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    SubscriberPlayerId = table.Column<long>(type: "INTEGER", nullable: false),
+                    TargetPlayerId = table.Column<long>(type: "INTEGER", nullable: false),
+                    CreatedAt = table.Column<DateTime>(type: "TEXT", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Subscriptions", x => x.Id);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Subscriptions_SubscriberPlayerId",
+                table: "Subscriptions",
+                column: "SubscriberPlayerId");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Subscriptions_SubscriberPlayerId_TargetPlayerId",
+                table: "Subscriptions",
+                columns: new[] { "SubscriberPlayerId", "TargetPlayerId" },
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Subscriptions_TargetPlayerId",
+                table: "Subscriptions",
+                column: "TargetPlayerId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Subscriptions");
+        }
+    }
+}