feat(education): complete student core loop delivery

tools/education-student-harness/run-playwright-if-available.js

@@ -0,0 +1,15 @@
+#!/usr/bin/env node
+'use strict';
+
+const { spawnSync } = require('child_process');
+const path = require('path');
+
+const cwd = __dirname;
+const result = spawnSync(process.execPath, ['-e', "try { require.resolve('@playwright/test'); require.resolve('playwright'); } catch (_) { process.exit(2); }"], { cwd, stdio: 'inherit' });
+if (result.status === 2) {
+  process.stdout.write('Playwright unavailable; dependency-free smoke/contract checks remain available.\n');
+  process.exit(0);
+}
+const command = process.platform === 'win32' ? 'npx.cmd' : 'npx';
+const run = spawnSync(command, ['playwright', 'test'], { cwd, stdio: 'inherit' });
+process.exit(run.status == null ? 1 : run.status);