fix(ci): keep fast bucket stable for commonjs tests

scripts/run-test-bucket.js

@@ -24,6 +24,12 @@ const slowTests = [
   'tests/unit/web-server/cursor-routes.test.ts',
   'tests/unit/web-server/websearch-routes.test.ts',
 ];
+// CommonJS-heavy JS suites stay slow by default because many of them mutate
+// module cache or process state. Opt them into `test:fast` only after they are
+// proven stable in the mixed fast bucket.
+const fastJsTests = new Set([
+  'tests/unit/flag-parsing-simple.test.js',
+]);
 
 const filePattern = /(\.test\.(c|m)?[jt]s|\.spec\.(c|m)?[jt]s|-test\.(c|m)?[jt]s)$/;
 
@@ -59,6 +65,10 @@ function shouldForceSlow(file) {
     return true;
   }
 
+  if (/\.(c|m)?js$/.test(file) && !fastJsTests.has(file)) {
+    return true;
+  }
+
   return readsBuiltDist(file);
 }
 
@@ -149,6 +159,7 @@ if (require.main === module) {
 
 module.exports = {
   slowTests,
+  fastJsTests,
   readsBuiltDist,
   shouldForceSlow,
   getDiscoveredTests,

tests/unit/scripts/run-test-bucket.test.js

@@ -18,6 +18,10 @@ describe('run-test-bucket', () => {
     expect(bucket.shouldForceSlow('tests/unit/flag-parsing-simple.test.js')).toBe(false);
   });
 
+  test('keeps non-allowlisted javascript tests in the slow bucket', () => {
+    expect(bucket.shouldForceSlow('tests/unit/commands/persist-command.test.js')).toBe(true);
+  });
+
   test('still forces dist-dependent tests into the slow bucket', () => {
     expect(bucket.shouldForceSlow('tests/unit/config-dir-override.test.js')).toBe(true);
   });