Suppress Node DEP0040 punycode warning in CLI startup

src/cli/suppressNodeWarnings.test.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it } from 'vitest';
+import { shouldSuppressNodeWarning } from './suppressNodeWarnings.js';
+
+describe('shouldSuppressNodeWarning', () => {
+  it('suppresses DEP0040 warning code', () => {
+    expect(shouldSuppressNodeWarning('DEP0040', 'any message')).toBe(true);
+  });
+
+  it('suppresses punycode deprecation by message text', () => {
+    expect(shouldSuppressNodeWarning(undefined, 'The `punycode` module is deprecated.')).toBe(true);
+  });
+
+  it('does not suppress unrelated warnings', () => {
+    expect(shouldSuppressNodeWarning('DEP0001', 'different deprecation')).toBe(false);
+  });
+});