Structure and changes detector

[vmc-crossmint]

Add checks for proper folder structure ( every folder must include CODEOWNERS and README.md). Add comment when changing a schema (schemas should be unmutable)

[github-actions[bot]]

Unexpected changes detected:

Unexpected change in schemas/categories/test/test, you should not update a schema file, consider creating a new version instead.

[github-actions[bot]]

Unexpected changes detected, you should not update a schema file, consider creating a new version instead.: : Unexpected change in schemas/categories/test/test