vault: implement bootstrap integration

CLAUDE.md

@@ -21,6 +21,16 @@ nixos-rebuild build --flake .#<hostname>
 nix build .#nixosConfigurations.<hostname>.config.system.build.toplevel
 ```
 
+**Important:** Do NOT pipe `nix build` commands to other commands like `tail` or `head`. Piping can hide errors and make builds appear successful when they actually failed. Always run `nix build` without piping to see the full output.
+
+```bash
+# BAD - hides errors
+nix build .#create-host 2>&1 | tail -20
+
+# GOOD - shows all output and errors
+nix build .#create-host
+```
+
 ### Deployment
 
 Do not automatically deploy changes. Deployments are usually done by updating the master branch, and then triggering the auto update on the specific host.