VariantData_TweetCountVariantData

Variant-specific metadata, discriminated by the type field.

Known variant types are deserialized into typed structs. Unknown variant
types are handled gracefully by the [deserialize_variant_data] helper
on parent structs so that new upstream types don't break deserialization.

{
    "type": "TWEET_COUNT",
    "xAccountUsername": "string",
    "tweetCount": 0
}