## Summary
This PR adds a new `lint` section to the configuration that groups all linter-specific settings. The existing top-level configurations continue to work without any warning because the `lint.*` settings are experimental.
The configuration merges the top level and `lint.*` settings where the settings in `lint` have higher precedence (override the top-level settings). The reasoning behind this is that the settings in `lint.` are more specific and more specific settings should override less specific settings.
I decided against showing the new `lint.*` options on our website because it would make the page extremely long (it's technically easy to do, just attribute `lint` with `[option_group`]). We may want to explore adding an `alias` field to the `option` attribute and show the alias on the website along with its regular name.
## Test Plan
* I added new integration tests
* I verified that the generated `options.md` is identical
* Verified the default settings in the playground

## Summary
We're planning to move the documentation from
[https://beta.ruff.rs/docs](https://beta.ruff.rs/docs) to
[https://docs.astral.sh/ruff](https://docs.astral.sh/ruff), for a few
reasons:
1. We want to remove the `beta` from the domain, as Ruff is no longer
considered beta software.
2. We want to migrate to a structure that could accommodate multiple
future tools living under one domain.
The docs are actually already live at
[https://docs.astral.sh/ruff](https://docs.astral.sh/ruff), but later
today, I'll add a permanent redirect from the previous to the new
domain. **All existing links will continue to work, now and in
perpetuity.**
This PR contains the code changes necessary for the updated
documentation. As part of this effort, I moved the playground and
documentation from my personal Cloudflare account to our team Cloudflare
account (hence the new `--project-name` references). After merging, I'll
also update the secrets on this repo.
## Summary
Document all `ruff_dev` subcommands and document the `format_dev` flags
in the formatter readme.
CC @zanieb please flag everything that isn't clear or missing
## Test Plan
n/a
## Summary
This PR adds a separate configuration file to enable us to turn on
[Insiders-only
plugins](https://squidfunk.github.io/mkdocs-material/insiders/getting-started/#built-in-plugins).
I've turned on the `typeset` plugin which ensures that the settings on
the left-hand navigation pane render as code:
<img width="1792" alt="Screen Shot 2023-07-05 at 6 27 20 PM"
src="c93676dd-bb48-417a-9d3b-528bf001e9b7">
Support for `let…else` formatting was just merged to nightly
(rust-lang/rust#113225). Rerun `cargo fmt` with Rust nightly 2023-07-02
to pick this up. Followup to #939.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>