User config parser that can fully roundtrip not to destroy user formatting

[eugenesvk]

If I want to have a properly formatted table in a json config file, for example, use tab/spaces to align keys separate vs values

{"context":"Workspace","bindings":{
  "ctrl-e"	:"command_palette::Toggle",
  "f1"    	:"dev::OpenKeyContextView",
  }

but then update a value to f2 in Zed GUI, this alignment is lost

  "f1"    	:"dev::OpenKeyContextView",
  "f2": "dev::OpenKeyContextView",

Instead Zed should use a json parser that is capable of properly roundtripping