* test: add current attachement responses
* refactor: check if attachement is linked and accessible by user
* chore: clean TODO
* fix: typo attachement -> attachment
* revert un-needed go.sum change
* refactor: move models logic to models
* fix TestCreateIssueAttachment which was wrongly successful
* fix unit tests with unittype added
* fix unit tests with changes
* use a valid uuid format for pgsql int. test
* test: add unit test TestLinkedRepository
* refactor: allow uploader to access unlinked attachement
* add missing blank line
* refactor: move to a separate function repo.GetAttachment
* typo
* test: remove err test return
* refactor: use repo perm for access checking generally + 404 for all reject
