refactor(services): delegate OrFail methods to non-throwing counterparts
- Refactor findByXOrFail methods to delegate to corresponding findByX methods
- Apply pattern across UserService, CompanyService, LevelService, RoleService, SkillService, UserJobExperienceService, OrganizationRoleService
- Remove code duplication and ensure consistent error handling
- OrFail methods now only handle the error-throwing responsibility