explain hugo docs site

hosts/proxy/README.md

@@ -58,6 +58,50 @@ HAProxy routes traffic using two methods:
 - TCP keep-alive enabled
 - Used for accessing legacy systems
 
+### Documentation Site (Hugo)
+
+The proxy hosts a self-documenting Hugo site at **docs.adm.htw.stura-dresden.de** that automatically builds from README files across the repository.
+
+**Architecture:**
+
+1. **Hugo Package Build** (in flake.nix):
+   - `docs-site` package built using `stdenv.mkDerivation`
+   - Uses Hugo static site generator with the hugo-book theme
+   - Script `docs/build-docs.sh` collects README files from:
+     - Main `README.md` → homepage
+     - `CLAUDE.md` → Claude Code guide page
+     - `hosts/*/README.md` → individual host documentation
+     - `keys/README.md` → key management guide
+   - Converts relative markdown links to work with Hugo's URL structure
+   - Builds static HTML site and stores it in the Nix store
+
+2. **Local Nginx Server**:
+   - Serves the Hugo site on localhost only (not directly accessible)
+   - HTTP on 127.0.0.1:8080
+   - HTTPS on 127.0.0.1:8443
+   - Uses ACME certificate for `docs.adm.htw.stura-dresden.de`
+   - Clean URL handling: `try_files $uri $uri/ $uri.html =404`
+
+3. **HAProxy Forwarding**:
+   - External requests to docs.adm.htw.stura-dresden.de forwarded to local nginx
+   - Entry in the `forwards` map routes port 80 → 8080, port 443 → 8443
+   - ACME challenges forwarded for automatic certificate renewal
+
+**Updating Documentation:**
+
+Just edit any README file in the repository and redeploy the proxy:
+```bash
+nix run .#proxy-update
+```
+
+The Hugo site will rebuild with the latest content from all README files.
+
+**Hugo Configuration:**
+- Config: `docs/hugo.yaml`
+- Theme: hugo-book v13 (alex-shpak/hugo-book)
+- Base URL: https://docs.adm.htw.stura-dresden.de/
+- Repository link: https://codeberg.org/stura-htw-dresden/stura-infra
+
 ### Auto-Generated Forwarding
 
 The proxy configuration is **partially auto-generated**:
@@ -262,6 +306,7 @@ This generates:
 The proxy currently forwards traffic for:
 
 **In this repository:**
+- docs.adm.htw.stura-dresden.de → 127.0.0.1 (Hugo documentation site, ports 8080/8443)
 - git.adm.htw.stura-dresden.de → 141.56.51.7 (Forgejo)
 - wiki.htw.stura-dresden.de → 141.56.51.13 (MediaWiki)
 - pro.htw.stura-dresden.de → 141.56.51.15 (Redmine)