feat: add delete by filter and update by filer to OpenSearchDocumentStore

[ChinmayBansal]

Related Issues

• fixes add update_by_filter() and delete_by_filter() operations to OpenSearchDocumentStore #2327

Proposed Changes:

Added delete_by_filter() and update_by_filter() methods to OpenSearchDocumentStore to enable bulk operations on filtered documents.

Implementation details:

• delete_by_filter(): Uses OpenSearch's delete_by_query API to efficiently delete documents matching filter criteria without retrieving them first
• update_by_filter(): Uses OpenSearch's update_by_query API with Painless scripts to update metadata fields for matching documents
• Returns count of affected documents for better observability
• Implements both sync and async versions for consistency with existing document store methods

Use cases:

• Bulk deletion based on metadata criteria (e.g., delete all documents older than a specific date)
• Bulk metadata updates (e.g., mark all documents in a category as "reviewed" or "published")
• Efficient document management without retrieving full documents first

Files changed:

• document_store.py: Added 4 methods (sync and async versions)
• test_document_store.py: Added 2 sync integration tests
• test_document_store_async.py: Added 2 async integration tests

How did you test it?

• ✅ Integration tests: Added 4 new integration tests:
  • test_delete_by_filter: Verifies selective deletion based on metadata filters
  • test_update_by_filter: Verifies metadata updates for filtered documents
  • test_delete_by_filter_async: Async version of delete test
  • test_update_by_filter_async: Async version of update test

Notes for the reviewer

• This is a new feature - first implementation of delete_by_filter() and update_by_filter()
• Used OpenSearch's native delete_by_query and update_by_query APIs for efficiency and performance
• The update_by_filter() method uses Painless scripting language to update metadata: ctx._source.metadata.{key} = params.{key}
• Filter normalization uses the existing normalize_filters() function to ensure consistency with filter_documents() method
• Both methods return affected document counts (from OpenSearch API response: result.get("deleted") and result.get("updated"))
• Tests include time.sleep(2) after operations to ensure changes are reflected (OpenSearch eventual consistency)

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added unit tests and updated the docstrings
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test:.