[Epic] Improve OASF class handling

[akijakya]

Refactor OASF to eliminate redundant category JSON files and improve class taxonomy handling. Remove skill_categories.json, domain_categories.json and module_categories.json files, building categories dynamically from class inheritance (extends relationships).
Improve API so it returns structured taxonomy for classes and improve per class requests (most endpoints require name, but should work with id and hierarchical name as well).
OASF SDK should also support the new API and provide support for translation API so class validation can be stricter by making both name and id a required field.