phase-7: code restructure

scripts/summary-reporter.ts

@@ -0,0 +1,48 @@
+// Minimal test reporter: silent on pass, prints failures in full, ends with one summary line.
+import type { TestEvent } from 'node:test/reporters';
+
+interface Failure {
+  name: string;
+  reason: string;
+}
+
+export default async function* summaryReporter(
+  source: AsyncIterable<TestEvent>,
+): AsyncGenerator<string> {
+  const failures: Failure[] = [];
+  let passed = 0,
+    failed = 0,
+    totalMs = 0;
+
+  for await (const event of source) {
+    // Skip file-level wrapper events (name ends in .ts) — only count individual tests.
+    if ((event.data as { name?: string })?.name?.endsWith('.ts')) continue;
+
+    if (event.type === 'test:pass') {
+      passed++;
+      totalMs += (event.data as { details?: { duration_ms?: number } }).details?.duration_ms ?? 0;
+    } else if (event.type === 'test:fail') {
+      failed++;
+      totalMs += (event.data as { details?: { duration_ms?: number } }).details?.duration_ms ?? 0;
+      const err = (
+        event.data as { details?: { error?: { cause?: { message?: string }; message?: string } } }
+      ).details?.error;
+      failures.push({
+        name: (event.data as { name?: string }).name ?? 'unknown',
+        reason: err?.cause?.message ?? err?.message ?? 'unknown',
+      });
+    }
+  }
+
+  if (failures.length) {
+    yield '\nFailed tests:\n';
+    for (const f of failures) yield `  ❌ ${f.name}\n     ${f.reason}\n`;
+    yield '\n';
+  }
+
+  const status = failed === 0 ? '✅' : '❌';
+  const time = (totalMs / 1000).toFixed(2);
+  yield `${status} ${passed + failed} tests: ${passed} passed`;
+  if (failed) yield `, ${failed} failed`;
+  yield `  (${time}s)\n`;
+}