Move style-spec docs to dedicated repo

[birkskyum]

Similar to the task related to the style-spec subfolder in maplibre gl js (maplibre/maplibre-gl-js#2149), the style-spec docs should also be split from the MapLibre GL JS docs. This is because the style-spec will have a different release cycle from maplibre-gl-js, and because the docs for these two packages are generated very differently:

• MapLibre GL JS is generated by parsing JSDoc comments
• Style Spec is a JSON document, so the docs are made in a very custom fashion.

Completion criteria:

• Make a clone of maplibre-gl-js-docs where everything but the style-spec code is removed.
• Use the files from the style-spec repo directly rather than a submodule or an npm package. It might be necessary to expose tsc compiled .js files, since batfish isn’t ts compatible.
• Deploy main branch with github pages to maplibre.org/maplibre-gl-style-spec
• Setup github action on PRs to test that docs can build
• Setup cloudflare redirect from old to new style-spec docs

[HarelM]

Link to bounty:
maplibre/maplibre#191

[birkskyum]

OC (XL bounty) https://opencollective.com/maplibre/expenses/135082

[wipfli]

@birkskyum delivered the work of the original scope in pull request #23. However, in the review of this pull request, the maintainer expanded the scope of work which resulted in pull request #88. Since the new scope was larger and included rewriting a new docs generation website, we added retroactively a bounty size XL to this ticket. This shall be a one-time exception and we require maintainers to not increase the scope of a bounty and developers to clarify design decisions before starting working on implementations.