This should help make sure we don't forget to document any important
user-visible changes.

Add [ruby-syntax-tree](https://github.com/ruby-syntax-tree/syntax_tree)
as an available formatter. Include support for finding a [`.streerc`
file](https://github.com/ruby-syntax-tree/syntax_tree#configuration).

---------

Co-authored-by: Radon Rosborough <radon@intuitiveexplanations.com>

Add [docformatter](https://github.com/PyCQA/docformatter) for Python
docstrings.

By default it outputs diffs but changes in-place with `--in-place`. On
successful change it exits with an error code of `3` (found out by
trial), so I had to add a formatter wrapping-script.

Initially I used `--in-place` with the special `in-place` symbol in
apheleia. But now I tried an approach where I transform the diff into
usable stdout using `patch` instead.

Related to #266 , where I had used the example of docformatter to ask
how to add scripts with positive exit codes and @raxod502 showed me the
`phpcs` solution.

---------

Co-authored-by: Radon Rosborough <radon@intuitiveexplanations.com>

Make it so that if there is a `.formatter.exs` file somewhere in the
parent directories, then Apheleia will run `mix format` from there
instead of the current directory.

Close #232

Gets all non-elisp dependencies into a single directory,
`scripts/formatters`

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This adds support for formatters installed locally in project
directories via yarn 2's "zero install" [pnp
mode](https://yarnpkg.com/features/pnp).

It's quite similar to the support for formatters installed locally in a
project's `node_modules` via npm, and leverages the `npx` symbol, so
existing formatter definitions should work without modification.

This checks for a `.pnp.cjs` file (expected in the project root for yarn
pnp projects), then looks for a yarn executable, and checks the version
of yarn to make sure it supports pnp. If that works, we just push
`"yarn"` onto the front of `command`.

I've only tested this with a locally installed `prettier.js`. It's very
much a works-for-me draft, I'm putting in a PR to make sure this is a
workable approach before going any further with it.

---------

Co-authored-by: Radon Rosborough <radon@intuitiveexplanations.com>

* feat: add emacs-lisp formatting

* Disable indent-tabs-mode

* Add stub file for installation

* Fix lint errors

* fix: correctly format based on previous mode

* Formatting

* Fix weird indent

* Add checkindent target

* Update changelog

* Long line

* Empty commit

* fix ci

* revert changelog reformatting

* more changelog

* more

Co-authored-by: Radon Rosborough <radon.neon@gmail.com>
Co-authored-by: Radon Rosborough <radon@intuitiveexplanations.com>

* feat: add phpcs & introduce scripts/formatters

Add phpcs as a supported formatter, and include support for
apheleia-defined scripts for more troublesome formatters

* Revert Emacs version requirement

* More quoting

* Adjust language in documentation

* Thanks checkdoc, lol

Co-authored-by: Radon Rosborough <radon.neon@gmail.com>

Closes #24
Builds on #25 by @PrimaryCanary