fix: fix vectordb

[zhoujh01]

Description

Related Issue

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

• Summary:
  This commit enhances the robustness of the fetch_cands_data logic in openviking/storage/vectordb/collection/local_collection.py.

Key Changes:

1. Data Consistency: It fixes a potential issue where data lists could become misaligned. The code now correctly identifies indices of valid (non-None)
   candidates and applies this filter synchronously to cands_list, pk_list (primary keys), and scores_list. Previously, None values might have been removed from
   the candidates list without updating the corresponding parallel lists.
2. Enhanced Logging: It adds warning logs when invalid (None) candidate data is encountered, which helps in debugging data integrity issues.

Testing

• 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
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Checklist

• My code follows the project's coding style
• I have performed a self-review of my 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
• Any dependent changes have been merged and published

Screenshots (if applicable)

Additional Notes