Ability to host Signatures locally

[zn-lab]

Is your feature request related to a problem? Please describe.
Currently signatures must be ingested from external source to AL4.
This might create an issue if you had not setup a publicly facing git repo.

Describe the solution you'd like
Ability to host signatures locally on the platform

Describe alternatives you've considered

Additional context
For example: Yara signatures we had to setup a dedicated git repo as an individual which is bad for RBAC.
@cccs-rs