## Summary
This PR adds documentation for the Ruff language server.
It mainly does the following:
1. Combines various READMEs containing instructions for different editor
setup in their respective section on the online docs
2. Provide an enumerated list of server settings. Additionally, it also
provides a section for VS Code specific options.
3. Adds a "Features" section which enumerates all the current
capabilities of the native server
For (2), the settings documentation is done manually but a future
improvement (easier after `ruff-lsp` is deprecated) is to move the docs
in to Rust struct and generate the documentation from the code itself.
And, the VS Code extension specific options can be generated by diffing
against the `package.json` in `ruff-vscode` repository.
### Structure
1. Setup: This section contains the configuration for setting up the
language server for different editors
2. Features: This section contains a list of capabilities provided by
the server along with short GIF to showcase it
3. Settings: This section contains an enumerated list of settings in a
similar format to the one for the linter / formatter
4. Migrating from `ruff-lsp`
> [!NOTE]
>
> The settings page is manually written but could possibly be
auto-generated via a macro similar to `OptionsMetadata` on the
`ClientSettings` struct
resolves: #11217
## Test Plan
Generate and open the documentation locally using:
1. `python scripts/generate_mkdocs.py`
2. `mkdocs serve -f mkdocs.insiders.yml`
It is apparently possible to add files to the git index, even if they
are part of the gitignore (see e.g.
https://stackoverflow.com/questions/45400361/why-is-gitignore-not-ignoring-my-files,
even though it's strange that the gitignore entries existed before the
files were added, i wouldn't know how to get them added in that case). I
ran
```
git rm -r --cached .
```
then change the gitignore not actually ignore those files with the
exception of
`crates/ruff_cli/resources/test/fixtures/cache_mutable/source.py`, which
is actually a generated file.