docs: make gen

Author: Tony Worm

docs/code/cmd-help/gen

@@ -66,7 +66,7 @@ hof unifies CUE with Go's text/template system and diff3
 
 # Compose code gen mappings into reusable modules with
   hof gen app.cue -G frontend -G backend -G migrations -T ...
-  https://docs.hofstadter.io/first-example/
+  https://docs.hofstadter.io/the-walkthrough/
 
 Usage:
   hof gen [files...] [flags]