feat: frontend Model extender (#3646)

* feat: reintroduce frontend extenders
* chore: used `Routes` extender in bundled extensions
* chore: used `PostTypes` extender in bundled extensions
* chore: `yarn format`
* feat: `Model` frontend extender
* chore: naming
* chore(review): attributes can be nullable or undefined
* chore(review): delay extender implementation
* chore(review): unnecessary check
* chore(review): stay consistent
* chore: merge conflicts
* chore: unused import
* chore: multiline extenders
* feat: add Store extender

Signed-off-by: Sami Mazouz <sychocouldy@gmail.com>

.editorconfig

@@ -18,7 +18,7 @@ trim_trailing_whitespace = false
 [*.{php,xml,json}]
 indent_size = 4
 
-[tsconfig.json]
+[{tsconfig.json,prettierrc.json}]
 indent_size = 2
 
 [*.neon]