build: establish strict TypeScript workspace

packages/contracts/src/index.test.ts

@@ -0,0 +1,8 @@
+import { describe, expect, it } from 'vitest';
+import { contractsWorkspaceReady } from './index.js';
+
+describe('contracts workspace baseline', () => {
+  it('exposes a compilable package entry', () => {
+    expect(contractsWorkspaceReady).toBe(true);
+  });
+});

packages/contracts/src/index.ts

@@ -0,0 +1 @@
+export const contractsWorkspaceReady = true;