CODE_STYLE.md: profess love for Json, Toml, and snake_case (rerun-io#…

…3350)

### Checklist
* [x] I have read and agree to [Contributor
Guide](https://github.com/rerun-io/rerun/blob/main/CONTRIBUTING.md) and
the [Code of
Conduct](https://github.com/rerun-io/rerun/blob/main/CODE_OF_CONDUCT.md)
* [x] I've included a screenshot or gif (if applicable)
* [x] I have tested [demo.rerun.io](https://demo.rerun.io/pr/3350) (if
applicable)

- [PR Build Summary](https://build.rerun.io/pr/3350)
- [Docs
preview](https://rerun.io/preview/505319ef6fd25235276b5e1394f3ae67227cac72/docs)
<!--DOCS-PREVIEW-->
- [Examples
preview](https://rerun.io/preview/505319ef6fd25235276b5e1394f3ae67227cac72/examples)
<!--EXAMPLES-PREVIEW-->
- [Recent benchmark results](https://ref.rerun.io/dev/bench/)
- [Wasm size tracking](https://ref.rerun.io/dev/sizes/)

CODE_STYLE.md

@@ -7,6 +7,13 @@
 * [`CONTRIBUTING.md`](CONTRIBUTING.md)
 * [`RELEASES.md`](RELEASES.md)
 
+## Languages
+We prefer Rust.
+
+We have a bunch of Bash and Python scripts that [we want to replace with Rust](https://github.com/rerun-io/rerun/issues/3349).
+
+For configs we like JSON and TOML, and [dislike YAML](https://ruudvanasseldonk.com/2023/01/11/the-yaml-document-from-hell).
+
 ## Rust code
 
 ### Avoid `unsafe`
@@ -116,6 +123,8 @@ Use debug-formatting (`{:?}`) when logging strings in logs and error messages. T
 Use `re_error::format(err)` when displaying an error.
 
 ## Naming
+We prefer `snake_case` to `kebab-case` for most things (e.g. crate names, crate features, …). `snake_case` is a valid identifier in almost any programming language, while `kebab-case` is not. This means one can use the same `snake_case` identifier everywhere, and not think about whether it needs to be written as `snake_case` in some circumstances.
+
 When in doubt, be explicit. BAD: `id`. GOOD: `msg_id`.
 
 Be terse when it doesn't hurt readability. BAD: `message_identifier`. GOOD: `msg_id`.