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/admin-ui/src/pages/Stub.tsx

@@ -0,0 +1,15 @@
+// Placeholder used by routes whose page hasn't been built yet so the
+// router/nav is wireable today and pages can land incrementally without
+// breaking links.
+
+export function Stub({ title, blurb }: { title: string; blurb?: string }) {
+  return (
+    <div className="space-y-3">
+      <h1 className="text-2xl font-semibold tracking-tight text-ink-50">{title}</h1>
+      <div className="card p-6 text-sm text-ink-300">
+        <div className="text-ink-200 mb-1">Coming soon.</div>
+        {blurb && <p className="text-ink-400">{blurb}</p>}
+      </div>
+    </div>
+  );
+}