git-crypt is great. I use it on a daily basis to encrypt code of some of my repositories. Some of the software I write contains industry secrets I don't want GitHub to know or train AI with. I don't trust them in keeping my private repos safe, so I use git-crypt. Honestly works way better than I expected initially. Once you configure it it's pretty seamless.
In your usecase, is a self-rolled Gitea not even more secure and also easier to use?
Who knows if your trade secrets get decrypted by an AI years from now