feat(horsch,zsh): add fu-build function

horsch/zsh.nix

@@ -14,6 +14,10 @@
       ssh smartcan "systemctl restart smartcan-''${1}"
     }
 
+    function fu-build {
+      ./kas-container build kas/kas-ttc-image-horsch.yml
+    }
+
     function fu-reboot {
       ssh fusion "reboot"
     }