I'm developing a Figma plugin that needs to import a large number of variables (600+) using the importVariableByKeyAsync API. However, I'm consistently receiving 429 Too Many Requests errors, even after implementing delays between requests.

Error Details
POST https://www.figma.com/api/response_sampler 429 (Too Many Requests)

Reproduction Steps
1.Attempted to import about 600+ variables using figma.variables.importVariableByKeyAsync(variable.key)
2.Even with asynchronous code and adding a 500ms delay between each request
3.Still receiving the 429 error after a certain number of requests

Questions
Does the Figma Plugin API have a rate limit for API calls?
What are the specific rate limits (requests per minute/hour)?
Is there an official recommended approach for handling bulk operations like importing many variables?
Are there any batch import methods available that I'm overlooking?