fix(cli): load default exports from JavaScript config

[jabrailkhalil]

When capacitor.config.js uses export default, Node returns a module namespace object. The CLI reads settings from that wrapper, so appId and appName become empty and webDir falls back to www.

Unwrap the default export using the same logic as the TypeScript config loader. Add regression tests that run the built config loader in a separate Node process, covering real ES modules and existing CommonJS configurations without Jest transforming the module format.

Fixes #8267.

Validation on Windows, Node 22.21.1:

• Original source: CommonJS case passes; ES module case fails with empty app identity and webDir: "www".
• CLI build passes.
• Config and framework-detection suites: 19 tests pass.
• ESLint, Prettier, and git diff --check pass.

Native Android/iOS builds and the full platform integration suite were not run.

[jabrailkhalil]

The CI workflows for the current head 08c356893b are waiting for contributor workflow approval (action_required): CI. Could a maintainer approve the pending runs when convenient? These runs have not executed their checks yet; I will address any failures once they run.