implemented 12-deployment.md: added systemd service generation (init --systemd) and migration guide from legacy script; introduced JSON-file persistence, server-rendered UI with polling, and reverse-proxy-based deployment; updated documentation

README.md

@@ -2,6 +2,18 @@
 
 Lightweight, declarative and highly opinionated software build system (CI/CD).
 
+## Documentation
+
+- [docs/configuration.md](docs/configuration.md) — configuration reference
+- [docs/bootstrapping.md](docs/bootstrapping.md) — initializing a repository with `init`
+- [docs/deployment.md](docs/deployment.md) — running GitTally as a systemd service behind a reverse proxy
+- [docs/migration-from-legacy.md](docs/migration-from-legacy.md) — migrating from the legacy bash script
+
+## Legacy Script
+
+`legacy/gitTally` (bash) is **deprecated** and kept only as a behavioral reference for the rewrite.
+Do not use it for new installations; see [docs/migration-from-legacy.md](docs/migration-from-legacy.md).
+
 ## Developer Setup
 
 Source `.envrc` to add `tools/` to your `PATH`, or install [direnv](#direnv) to have this done automatically on `cd`: