Add browser-only editor export and 2.5D runtime presentation

tests/presentation.test.ts

@@ -0,0 +1,24 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { normalizeHud } from "../engine/presentation.ts";
+test("HUD bounds script values and handles malformed meter entries", () => {
+  const h = normalizeHud({
+    objective: "x".repeat(300),
+    counters: [1, 2, 3, 4, 5],
+    meters: [
+      null,
+      { id: "life", max: 5, value: 12, style: "hearts" },
+      { max: 0, value: NaN },
+      { max: 10, value: -3 },
+    ],
+  });
+  assert.equal(h.objective!.length, 180);
+  assert.equal(h.counters!.length, 4);
+  assert.equal(h.meters![0].value, 0);
+  assert.equal(h.meters![1].value, 5);
+  assert.equal(h.meters![1].style, "hearts");
+  assert.equal(h.meters![2].max, 1);
+  assert.equal(h.meters![3].value, 0);
+  assert.deepEqual(normalizeHud(null), {});
+  assert.equal(normalizeHud({ overlay: null }).overlay, null);
+});