flake(shells): add ad-hoc cmds [skip ci]

flake.nix

@@ -119,6 +119,14 @@
               (import ./overlay.nix)
             ];
           };
+          gob = pkgs.writeShellScriptBin "gob" ''
+            cd $(git rev-parse --show-toplevel)
+            go build -v ./...
+          '';
+          gota = pkgs.writeShellScriptBin "gota" ''
+            cd $(git rev-parse --show-toplevel)
+            go test ./...
+          '';
         in
         {
           default = with pkgs; mkShell
@@ -152,6 +160,10 @@
                 goPkgs.patchelf-x86_64
                 goPkgs.patchelf-aarch64
 
+                ## ad-hoc cmds
+                gob
+                gota
+
                 gopls
                 gofumpt
                 go-tools