Harden settler runtime and scaffold tests

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

@@ -0,0 +1,23 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+
+const dir = path.resolve(__dirname, '../../examples');
+
+function loadJson(file) {
+  return JSON.parse(fs.readFileSync(path.join(dir, file), 'utf8'));
+}
+
+test('examples package exists for settler', () => {
+  for (const file of ['README.md', 'basic.flow.json', 'integration.flow.json', 'edge.flow.json']) {
+    assert.equal(fs.existsSync(path.join(dir, file)), true, file + ' missing');
+  }
+});
+
+test('example flows are parseable arrays for settler', () => {
+  for (const file of ['basic.flow.json', 'integration.flow.json', 'edge.flow.json']) {
+    const parsed = loadJson(file);
+    assert.equal(Array.isArray(parsed), true);
+  }
+});