Improve json detection for formatted text

[Pablete1234]

Currently we only parse xml strings as json if the strictly start with {" and end with "}, this works fine for strings like: {"text": "a", "color": "red"} but fails very quickly when you try to do anything slightly more complex like {text:"a",clickEvent:{...}}, since neither the start nor the end will have a " following the }. Furthermore we can't really relax the constraint for the " since we may have strings like {teamA} - {teamB} using replacements to fill in variables.

This pr instead uses a regex to see if it's looking a bit more json-like, checking for it strictly:

• Starting with [ or {, with potentially many of them and spaces in the middle
• Followed by "property" or 'property' or simply property (with matching start/end quotes)
• Followed by :
• Ending in one or many of ] or }

I think the logic for trying to match for a first property-looking text with a : separator should be enough to catch all valid jsons and avoid matching non-json strings, which need to have diff treatment