P10.2: convert remaining dashboardAPI tests from Mocha to node:test

P6.7 converted test/basic/. Convert test/edge/ and test/integration/ the
same way: describe/it/expect → test/assert. No behavioural change.

5 / 5 tests pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

test/edge/structure-examples-node-type.edge.test.js

@@ -1,11 +1,11 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
 const fs = require('node:fs');
 const path = require('node:path');
 
 const flow = JSON.parse(fs.readFileSync(path.resolve(__dirname, '../../examples/basic.flow.json'), 'utf8'));
 
-describe('dashboardAPI edge example structure', () => {
-  it('basic example includes node type dashboardapi', () => {
+test('basic example includes node type dashboardapi', () => {
   const count = flow.filter((n) => n && n.type === 'dashboardapi').length;
-    expect(count).toBeGreaterThanOrEqual(1);
-  });
+  assert.ok(count >= 1, `expected ≥1 dashboardapi node, got ${count}`);
 });

test/integration/structure-examples.integration.test.js

@@ -1,3 +1,5 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
 const fs = require('node:fs');
 const path = require('node:path');
 
@@ -7,17 +9,15 @@ function loadJson(file) {
   return JSON.parse(fs.readFileSync(path.join(dir, file), 'utf8'));
 }
 
-describe('dashboardAPI integration examples', () => {
-  it('examples package exists for dashboardAPI', () => {
+test('examples package exists for dashboardAPI', () => {
   for (const file of ['README.md', 'basic.flow.json', 'integration.flow.json', 'edge.flow.json']) {
-      expect(fs.existsSync(path.join(dir, file))).toBe(true);
+    assert.ok(fs.existsSync(path.join(dir, file)), `missing ${file}`);
   }
 });
 
-  it('example flows are parseable arrays for dashboardAPI', () => {
+test('example flows are parseable arrays for dashboardAPI', () => {
   for (const file of ['basic.flow.json', 'integration.flow.json', 'edge.flow.json']) {
     const parsed = loadJson(file);
-      expect(Array.isArray(parsed)).toBe(true);
+    assert.ok(Array.isArray(parsed), `${file} is not an array`);
   }
 });
-});