Consider whether to include public/index.html template as part of @edx/frontend-build

This package currently expects the consuming application to have an existing public/index.html template (it will error otherwise).

We may want to explore whether it's possible and/or makes sense to have a default public/index.html template contained within @edx/frontend-build itself so that consuming applications do not need to worry about maintaining their own public/index.html.

However, if an application needs to override a default public/index.html template, it should still be possible to use the public/index.html template from the consuming application.

We should also consider whether this default public/index.html template includes a favicon. For edX microfrontends, the favicon is likely to be the edX logo (eventually pulled from the @edx/brand package), but it likely doesn't make sense to include @edx/brand as a peer dependency of this package, such that @edx/frontend-build remains agnostic.

Review how @edx/frontend-build currently expects the consuming application’s public/index.html template and identify the relevant build behavior. Clarify whether a bundled default should exist, how an application override would work, and whether the default should include a favicon or remain independent of @edx/brand.