This separation introduced in I8dbc29b7a19f7f doesn't work as well
as expected. All but strictly `.mw-jump-link` rule are typographic
rules.
In the current mish-mash of when to apply typographic styles only to
article content (`.mw-body`, `mw-body-content`, `.mw-parser-output`,
`#mw-data-after-content`?) inherited from core, it makes looking up
and finding issues between typographic styles harder, and leads to
unnecessary complexity instead of clean separation of concerns.
This question surfaced in where would link styles belong originated in
T213778.
Change-Id: I521185d505d8688f076dd09acbedb22e801f772e
Using 'skin' as entrance point files, similar to already existing
convention in MediaWiki land with 'skin.json' or 'SkinVector.php' as
example in Vector skin. Replacing Apache inspired 'index' convention.
Also renaming legacy to 'skin-legacy' to be clear on file base that it's
a modification of 'skin'.
Bug: T249073
Change-Id: Ief1c469724d4ffe238d307407c3ddb46f2e1abfa
Volker E