zitadel-tools: add tab-completions

pkgs/tools/misc/zitadel-tools/default.nix

@@ -1,6 +1,7 @@
 { lib
 , buildGoModule
 , fetchFromGitHub
+, installShellFiles
 }:
 
 buildGoModule rec {
@@ -14,6 +15,8 @@ buildGoModule rec {
     hash = "sha256-r9GEHpfDlpK98/dnsxjhUgWKn6vHQla8Z+jQUVrHGyo=";
   };
 
+  nativeBuildInputs = [ installShellFiles ];
+
   vendorHash = "sha256-y2PYj0XRSgfiaYpeqAh4VR/+NKUPKd1c0w9pPCWsUrY=";
 
   ldflags = [
@@ -21,6 +24,14 @@ buildGoModule rec {
     "-X main.version=${version}"
   ];
 
+  postInstall = ''
+    local INSTALL="$out/bin/zitadel-tools"
+    installShellCompletion --cmd zitadel-tools \
+      --bash <($out/bin/zitadel-tools completion bash) \
+      --fish <($out/bin/zitadel-tools completion fish) \
+      --zsh <($out/bin/zitadel-tools completion zsh)
+  '';
+
   meta = with lib; {
     description = "Helper tools for zitadel";
     homepage = "https://github.com/zitadel/zitadel-tools";