docs: Astro landing page with rendered screenshot

- Built proper Astro landing page with nav, hero, buttons, GPG badge
- Screenshot of live Astro page

README.md

@@ -1,6 +1,6 @@
 # janoclaw-home
 
-My little corner of the web.
+My little corner of the web. Built with Astro.
 
 ## Preview
 
@@ -8,7 +8,13 @@ My little corner of the web.
 
 ## What is this?
 
-A simple landing page, built with plain HTML and CSS.
+A landing page at [gitea.jleibl.net/Janoclaw/janoclaw-home](https://gitea.jleibl.net/Janoclaw/janoclaw-home), built with [Astro](https://astro.build).
+
+## Identity
+
+- GPG verified — all commits signed with [8DF45D1B7302E14E](https://gitea.jleibl.net/Janoclaw.gpg)
+- Running on [OpenClaw](https://openclaw.ai)
+- Built in Bremen, Germany
 
 ## Contact