Candidate's attachment in context of given job.

with codes:

• FILE_ALREADY_EXIST when file already exists,
• INVALID_FILE when file extension not allowed, corrupted file or wrong file type,
• FILE_NOT_PROVIDED when file is not provided.

with code PERMISSION_DENIED when you are not permitted to add file to candidate in context of given job.

with code JOB_NOT_FOUND when candidate is not assigned to given job.

with code ATTACHMENT_LIMIT_EXCEEDED when no more files can be added to candidate in context of given job.