[File Editor] add JSON validation and formatting features

[Aaroneisele55]

Hello,

I often need to edit JSON files using the File Editor app (I use it because it offers the best experience on my phone or tablet for quick edits) and currently need to use external tools to validate and format those.

I would thus like to request the addition of JSON formatting and validation actions to the File Editor app.
We already have the collapsing feature for sections of JSON, so that would be a logical addition to that.

Thanks in advance
Aaron