feat(oxfmt): .editorconfig support

[Boshen]

closes #15850

@leaysgur handing this over to you, because we need a bigger change to merge the options.

https://github.com/prettier/prettier/blob/1cc636785661d9c0b53a31845348ed0d5456211b/src/config/resolve-config.js#L74-L86

If you look at the TODO line, we need to create default options, then override it by editorconfig, then override by oxfmtrc.json

.editorconfig defines overrides already

[*]
charset = utf-8
trim_trailing_whitespace = true
end_of_line = lf
insert_final_newline = true
indent_style = space
indent_size = 4

[*.{js,mjs,cjs,jsx,ts,tsx,json,yml}]
indent_size = 2

So each path receives a different config. I think you may want to plan ahead for oxfmtrc override, which should behave exactly the same as editorconfig.

[codspeed-hq]

CodSpeed Performance Report

Merging #16680 will not alter performance

_{Comparing 12-10-feat_oxfmt_.editorconfig_support (fcc8dd8) with main (8babdf9)¹}

Summary

✅ 42 untouched
⏩ 3 skipped²

Footnotes

1. No successful run was found on main (0a3bb7b) during the generation of this report, so 8babdf9 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩