Seed VS Code test user settings in .vscode-test.mjs for local parity

[Copilot]

A review comment flagged that local smoke-test / e2e-test / integration-test runs depended on CI-only setup for python.useEnvironmentsExtension. This updates test config initialization so the required user setting is provisioned directly by .vscode-test.mjs.

• Problem addressed

  • Local runs could skip extension activation because .vscode-test/user-data/User/settings.json was not created outside CI.

• Change

  • In .vscode-test.mjs, create User/settings.json under the configured --user-data-dir and write:
    • "python.useEnvironmentsExtension": true

• Resulting behavior

  • Test entrypoints now initialize the same required setting in local and CI contexts without relying on external workflow steps.

const userSettingsFile = path.join(userDataDir, 'User', 'settings.json');

fs.mkdirSync(path.dirname(userSettingsFile), { recursive: true });
fs.writeFileSync(
  userSettingsFile,
  JSON.stringify({ 'python.useEnvironmentsExtension': true }),
);