add updateSettings drv which will union nix settings configurations into the a vscode settings file

pkgs/misc/vscode-extensions/updateSettings.nix

···
+# Updates the vscode setting file base on a nix expression
+# should run from the workspace root.
+{ writeShellScriptBin
+, lib
+, jq
+}:
+##User Input
+{ settings      ? {}
+# if marked as true will create an empty json file if does not exists
+, createIfDoesNotExists ? true
+, vscodeSettingsFile ? .vscode/settings.json
+}:
+let
+  #VSCode Settings file
+  vscodeSettingsFileStr = toString vscodeSettingsFile;
+
+  updateVSCodeSettingsCmd = ''
+  (
+    echo 'updateSettings.nix: Updating ${vscodeSettingsFileStr}...' 
+    oldSettings=$(cat ${vscodeSettingsFileStr})
+    echo $oldSettings' ${builtins.toJSON settings}' | ${jq}/bin/jq -s add > ${vscodeSettingsFileStr}
+  )'';
+
+  createEmptySettingsCmd = ''mkdir -p .vscode && echo "{}" > ${vscodeSettingsFileStr}'';
+in 
+  writeShellScriptBin ''vscodeNixUpdate-${lib.removeSuffix ".json" (builtins.baseNameOf vscodeSettingsFileStr)}''
+  (lib.optionalString (settings != {}) 
+  (if createIfDoesNotExists then ''
+    [ ! -f "${vscodeSettingsFileStr}" ] && ${createEmptySettingsCmd}
+    ${updateVSCodeSettingsCmd}
+  ''
+  else ''[ -f "${vscodeSettingsFileStr}" ] && ${updateVSCodeSettingsCmd}''
+  ))

pkgs/misc/vscode-extensions/updateSettingsTest.nix

···
+with import <nixpkgs>{};
+callPackage (import ./updateSettings.nix) {} {
+  settings = {
+    a = "fdsdf";
+  };
+}