test(layouts): suggestedPresets references must resolve to registered presets

Phase F.2 (audit portion) of the rule-variants epic.

Adds a suite to premades.test.ts that walks every layout's
`suggestedPresets` and verifies each referenced id resolves to a
registered preset. Catches rename / deletion drift before a
dangling chip surfaces in the lobby UI.

Current audit is green: all 7 suggestedPresets entries across
dual-classic, knightmate, pawns-only, and monster reference real
ids. (UI 'suggested rules chip' rendering is a separate follow-up
bundled with the Phase F.3 RulesDrawer work.)

Tests: 1651 passing (was 1650, +1 new audit test).

packages/chess/src/layouts/premades.test.ts

@@ -10,6 +10,8 @@ import { LAYOUT_REGISTRY } from "./registry.js";
 import { validateLayout } from "./validate.js";
 import { EMPTY_LAYOUT } from "./empty.js";
 import "./index.js"; // trigger registration of every premade
+import { PRESET_REGISTRY } from "../presets/registry.js";
+import "../presets/index.js"; // trigger preset registration
 
 describe("LAYOUT_REGISTRY — premade roster", () => {
   it("includes every expected id", () => {
@@ -79,3 +81,24 @@ describe("premade piece counts", () => {
     });
   }
 });
+
+// Phase F.2: every entry in a layout's `suggestedPresets` must
+// reference a REAL registered preset id. Catches renames / deletions
+// before the UI surfaces a dangling chip.
+describe("suggestedPresets → preset-id integrity", () => {
+  it("every suggestedPresets entry references a registered preset", () => {
+    const presetIds = new Set(PRESET_REGISTRY.getAll().map((p) => p.id));
+    const dangling: string[] = [];
+
+    for (const layout of LAYOUT_REGISTRY.list()) {
+      const suggested = layout.suggestedPresets ?? [];
+      for (const ref of suggested) {
+        if (!presetIds.has(ref)) {
+          dangling.push(`"${layout.id}" → "${ref}" (unknown preset)`);
+        }
+      }
+    }
+
+    expect(dangling).toEqual([]);
+  });
+});