Update extension readme and style guideline (#348)

* docs: update how to use coding guidelines extension roles

* docs: update style-guideline with more fleshed out example guideline

* fix: remove space inside inline code

* fix: add compilability to typos config

Author: PLeVasseur

_typos.toml

@@ -8,3 +8,6 @@ extend-ignore-identifiers-re = [
   "bib_.*",
 ]
 
+[default.extend-words]
+# Allow domain-specific terms
+compilability = "compilability"