Make all json dynamic autocomplete only show up when in strings

[Xterionix]

Like texture paths shouldn't show up inside of. This'd have to be specified for the different completions as it may be applicable in some places

{ "textures": {|} }

But it should here

{ "textures": {"default": "|"} }

[Xterionix]

Additionally, if it could check if the cursor is in the property or value, that'd be great too