The `msapplication` tile configuration serves no purpose now, so the
`browserconfig.xml` it points at, the five tile images and the two meta tags
in `index.html` are removed together.
`shared-docs/icons/twitter.svg` is also unused, left behind when the footer
moved to X and Bluesky. Its three siblings in that directory are all still
referenced.
To increase the ease of development we are moving @angular/docs into the adev directory within this repo. While
we are doing this to improve our development experience in the short term, efforts are also in place
to maintain a division between this @angular/docs (shared) code and adev itself, so that it can be extracted
back out in the future when components is ready to leverage it as well.
PR Close#57132