chore: repoint URLs at git.swaits.com and bump for release

Rewrites remaining github.com / git.sr.ht references to git.swaits.com,
translating GitHub URL shapes to Gitea's (/blob/<ref>/ -> /src/branch/<ref>/,
/tree/<tag> -> /src/tag/<tag>, /actions/workflows/X -> /actions?workflow=X,
/edit/ -> /_edit/).

Left pointing at GitHub on purpose: pull-request links (PRs were not migrated)
and GitHub-only surfaces Gitea lacks (security advisories, discussions).

CHANGELOG.md

@@ -24,5 +24,5 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Self-recursion guard via `FUCKGIT_DEPTH` env counter (aborts at depth ≥ 2).
 - Linux and macOS support. Zero runtime dependencies.
 
-[Unreleased]: https://github.com/swaits/fuckgit/compare/v0.1.0...HEAD
-[0.1.0]: https://github.com/swaits/fuckgit/releases/tag/v0.1.0
+[Unreleased]: https://git.swaits.com/swaits/fuckgit/compare/v0.1.0...main
+[0.1.0]: https://git.swaits.com/swaits/fuckgit/releases/tag/v0.1.0