Post a cast

curl --request POST \
  --url https://api.neynar.com/v2/farcaster/cast \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '{
  "signer_uuid": "19d0c5fd-9b33-4a48-a0e2-bc7b0555baec",
  "text": "Writing to @farcaster via the @neynar APIs 🪐"
}'

{
  "success": true,
  "cast": {
    "hash": "0xfe90f9de682273e05b201629ad2338bdcd89b6be",
    "author": {
      "fid": 3
    },
    "text": "<string>"
  }
}