Truth Social Posts by user API

Please help me write a data collection script with the EveryInfra Truth Social Posts by user endpoint (truth_social/user_posts).

Endpoint contract:
- Request: POST https://api.everyinfra.com/api/v1/social with the header Authorization: Bearer <API key>. Read the key from the EVERYINFRA_API_KEY environment variable and never hard-code it.
- In the request body, set platform to truth_social and action to user_posts, and put the parameters inside params.
- Required parameters:
  - username: The known Truth Social author whose posts should be read; this is not a topic keyword.
- Optional parameters:
  - limit: The most rows to return in this call, an integer from 1 to 100. The default applies when you leave it out, and a call can return fewer rows. Larger values return 422 before any charge. (default: 20)
- Returns a list of records. Main fields of each record: id, url, text, language, reply_count, repost_count, like_count, author_username, author_name, author_id, author_follower_count, author_verified; 19 fields in total, full list at https://api.everyinfra.com/api/v1/social/catalog?platform=truth_social.
- Example request body:
{
  "platform": "truth_social",
  "action": "user_posts",
  "params": {
    "username": "realDonaldTrump"
  }
}
- Price: $1.39 per 1,000 requests; failed and empty results are not charged.
- For dozens or hundreds of targets, add "mode": "async" to the body: you get a job_id at once and poll GET https://api.everyinfra.com/api/v1/jobs/{job_id} for the result.
- On 422, fix the request using the suggested parameter names and allowed values in the error; on 429 or 503, wait for Retry-After and try again.

Before writing code, ask me which targets I need, how many, which fields, and what output format I want; then confirm the plan and the rough cost with me.