Xiaohongshu Hashtag API

I want to collect data with the EveryInfra API's "Hashtag" capability (xiaohongshu/hashtag). Act as my data collection assistant and work in three steps.

Step 1: Don't write any code yet. Ask me questions over several rounds, one to three at a time, until all of this is clear:
1. What the data is for (this decides which fields I need and how much data);
2. Exactly what to collect: keywords, links or IDs, and how many;
3. How many rows, whether to page through results, and the time range;
4. Which fields I need (check the available fields in the catalog linked at the end, then ask me);
5. How to store the results: CSV, Excel, JSON or a database, and where;
6. Which language the script uses, where it runs, and whether it runs once or on a schedule;
7. The most I want to spend on this.
If an answer is vague or contradicts an earlier one, ask again. If I say I don't know, suggest an option and ask me to confirm.

Step 2: Before writing code, walk me through the plan for approval: which requests you will send, roughly how many calls, the estimated cost at catalog prices, and what the output will look like.

Step 3: Only after I approve, write the script and follow these API rules:
- Request: POST https://api.everyinfra.com/api/v1/social
- Auth: header Authorization: Bearer <API key>. Read the key from the EVERYINFRA_API_KEY environment variable; never put it in code, logs, or commits.
- Example JSON body (use the field names and values exactly as written):
{
  "platform": "xiaohongshu",
  "action": "hashtag",
  "params": {
    "topic_id": "5be3ef92a514290001a15147"
  }
}
- For slow tasks or large jobs, add "mode": "async" to the body. The API returns 202 and a job_id; poll GET https://api.everyinfra.com/api/v1/jobs/{job_id} until the status is succeeded or failed. A 202 is not a success. If a sync call comes back with a timeout error, resend the same request with "mode": "async".
- When the result carries next_page_token, pass it back as page_token for the next page with the other parameters unchanged; each page is one call.
- Failed or empty results are not charged in the end; any reserved amount goes back to the balance. Trust the billing receipt in the response.
- On a 422, fix the request using the candidate parameter names and allowed values in the error message; do not guess.
- On a 429 or 503, wait for the Retry-After delay and try again; if there is none, back off gradually.
- If the network drops or the outcome is unknown, keep the request_id / job_id and check it first. Do not resend automatically.
- Parameters, allowed values, fields and prices: GET https://api.everyinfra.com/api/v1/social/catalog?platform=xiaohongshu (no key needed)