feat: Add input folder support for batch api

[boqiny]

Description

Previous batch api only accepts single file input, which is just like a super long async function.
Now refer to OpenAI's batch API implementation https://platform.openai.com/docs/guides/batch/getting-started?lang=node
We should add for a folder support by:

1. First upload the contents in the folder and save the filename and requestId as jsonl (shown in examples/parse_batch_upload.py)
2. Use generated jsonl to get the markdown for each elements when finished (shown in examples/parse_batch_fetch.py)

Now I set max worker = 10 & max input folder size = 1000

Related Issue

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Performance improvement

How Has This Been Tested?

Test scripts being added to examples folder parse_batch_upload.py and parse_batch_fetch.py

Screenshots (if applicable)

Generated Json after upload input folder

Fetch (Added markdown contents after processing is finished)

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Additional Notes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

examples/parse_batch_fetch.py:14

• The variable name MAX_WORKER should be renamed to MAX_WORKERS for consistency.

MAX_WORKER = 10

README.md:87

• The example code is missing the step to read the request ID from the response. It should be updated for clarity.

markdown = ap.batches.retrieve(request_id)

Replace print statement with a proper logging mechanism for error handling.

Suggested change

	print(f"Error processing {request_id}: {str(e)}")
	logging.error(f"Error processing {request_id}: {str(e)}")

[lingjiekong]

There is no need to restrict on this. For the batch API, the logic is that

• there is a crone job for every 2 hour
• there is a scan every 5 mins and if the batch queue size is more than 1000
  One of the two situation match will trigger a batch run.

[lingjiekong]

not need for this.

[lingjiekong]

Rule of thumb is that it is better to return a list of UploadResponse instead of a awkward file path that people have to know what this means and read it in.