Rework project formatting tools.

* Changes JS formatting policy to expect trailing commas in most of the places they're allowed.
* Moves format checking out of `npm` and into tool scripts.
* _Documents_ formatting tools, as well as a shot at a policy for format-only changes designed to alleviate low-value review.

This was originally part of [another proposal][pr-6]. I've broken it out to make the intent clearer, and to make the proposal easier to get a handle on in isolation from other, related changes. Thanks to @wlonk for their input on this!

[pr-6]: https://codeberg.org/ojacobson/pilcrow/pulls/6

Merges prop/project-formatting into main.

1 files changed, 10 insertions, 0 deletions

diff --git a/tools/reformat b/tools/reformat
new file mode 100755
index 0000000..4dfe7c3
--- /dev/null
+++ b/tools/reformat
@@ -0,0 +1,10 @@
+#!/bin/bash -e
+
+## tools/reformat
+##
+## Automatically reformats code in this project to match the project style.
+
+cd "$(dirname "$0")/.."
+
+npx prettier --write .
+cargo fmt --all