test_runner: apply default test-file exclusion via run() API

The CLI path defaults coverageExcludeGlobs to [kDefaultPattern] when
--experimental-test-coverage is set, dropping test files from the
coverage report. The run() API skipped this default, so callers got
test files mixed into their coverage data. Apply the same default
when run() is invoked with coverage: true and no explicit
coverageExcludeGlobs, so both entry points behave consistently.

Update the existing run() coverage tests that depended on the absent
default to opt out via coverageExcludeGlobs: '!test/**'.

Refs: #60023
Signed-off-by: sangwook <rewq5991@gmail.com>

Author: Han5991

lib/internal/test_runner/runner.js

@@ -805,6 +805,8 @@ function run(options = kEmptyObject) {
       coverageExcludeGlobs = [coverageExcludeGlobs];
     }
     validateStringArray(coverageExcludeGlobs, 'options.coverageExcludeGlobs');
+  } else if (coverage) {
+    coverageExcludeGlobs = [kDefaultPattern];
   }
   if (coverageIncludeGlobs != null) {
     if (!ArrayIsArray(coverageIncludeGlobs)) {

test/parallel/test-runner-run-coverage.mjs

@@ -123,6 +123,7 @@ describe('require(\'node:test\').run coverage settings', { concurrency: true },
       const stream = run({
         files,
         coverage: true,
+        coverageExcludeGlobs: '!test/**',
         coverageIncludeGlobs: ['test/fixtures/test-runner/coverage.js', 'test/*/v8-coverage/throw.js'],
       });
       stream.on('test:fail', common.mustNotCall());
@@ -157,7 +158,14 @@ describe('require(\'node:test\').run coverage settings', { concurrency: true },
       const thresholdErrors = [];
       const originalExitCode = process.exitCode;
       assert.notStrictEqual(originalExitCode, 1);
-      const stream = run({ files, coverage: true, lineCoverage: 99, branchCoverage: 99, functionCoverage: 99 });
+      const stream = run({
+        files,
+        coverage: true,
+        coverageExcludeGlobs: '!test/**',
+        lineCoverage: 99,
+        branchCoverage: 99,
+        functionCoverage: 99,
+      });
       stream.on('test:fail', common.mustNotCall());
       stream.on('test:pass', common.mustCall(1));
       stream.on('test:diagnostic', ({ message }) => {