bug(nimbus-fml): Add type_name for JsonObject in uniffi.toml

[relud]

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[bendk]

You're kind of treading new ground here, normally this is just a simple type name. I think it should work, but I guess we'll see when this gets to the experimenter CI.

FWIW, it's possible that loads returns a JSON object with integer keys, or for that matter just an integer. However, I don't think that will happen with the ones nimbus-fml is sending and in any case, this is just used for the typecheckers.

So, there's a couple things that may go wrong but I'm still for merging this one and see what happens when you run pyright on the generated code.

[relud]

normally this is just a simple type name

CI threw NameError: name 'Any' is not defined, so I reduced it to dict