fix: require runtime evidence in budget gate

tests/performance/runtime-budget-trace.spec.ts

@@ -1,4 +1,5 @@
 import { writeFile } from 'node:fs/promises';
+import { resolve } from 'node:path';
 import { expect, test } from '../helpers/serve-dist';
 import { authorizedPerformanceUrl } from '../helpers/test-build-auth';
 import {
@@ -48,9 +49,13 @@ test('runtime-budget-trace.v1 captures the actual High production allocation at
   };
   const evaluated = validateRuntimeBudgetTraceReport(report);
   expect(evaluated.violations).toEqual([]);
-  await writeFile(testInfo.outputPath('runtime-budget-trace.v1.json'), `${JSON.stringify({
+  const serialized = `${JSON.stringify({
     ...report,
     runtimeBudgetSummary: evaluated.tier,
     violations: evaluated.violations,
-  }, null, 2)}\n`);
+  }, null, 2)}\n`;
+  await Promise.all([
+    writeFile(testInfo.outputPath('runtime-budget-trace.v1.json'), serialized),
+    writeFile(resolve('test-results/runtime-budget-trace.v1.json'), serialized),
+  ]);
 });