Point links at git.coffeylabs.org after the move from GitHub

GitHub took the organization's repos and GHCR offline on 2026-09-20. Repo,
release, raw-file and clone links now go to Gitea at git.coffeylabs.org,
container images to registry.coffeylabs.org, and GitLab-style /-/blob paths
to Gitea's /src/branch form. Go module paths are identifiers and stay as
they are; links to GitHub issues and pull requests are left as history.

SECURITY.md

@@ -35,8 +35,8 @@ to Stalwart Labs with credit to you, and you'll be told that has happened.
 
 This repository is the mail server. The web front ends have their own:
 
-- [inbuxa-admin](https://github.com/inbuxa/inbuxa-admin)
-- [ihasmail-inbuxa](https://github.com/inbuxa/ihasmail-inbuxa)
+- [inbuxa-admin](https://git.coffeylabs.org/inbuxa/inbuxa-admin)
+- [ihasmail-inbuxa](https://git.coffeylabs.org/inbuxa/ihasmail-inbuxa)
 
 Upstream's own security documents are kept in `.github-upstream/` for
 reference. They describe Stalwart Labs' process, not this project's.