Enhancement: bulk prefetch IOCs before processing to eliminate per-IOC SELECT queries. Closes #1241

[rahulgunwanistudy-2005]

Description

The extraction pipeline was calling ioc_repo.get_ioc_by_name() once per IOC inside add_ioc(), so a batch of U unique IPs meant U SELECT queries. On top of that, _add_fks() in BaseExtractionStrategy was re-fetching IOCs that add_ioc() had just processed. Tanner had a manual local ioc_cache in _classify_attacks() as a partial workaround for the same problem.

This PR fixes all three by introducing a bulk prefetch mechanism in IocProcessor:

• Added _ioc_cache and prefetch_iocs() to IocProcessor. Each _get_scanners() now bulk-loads all IOCs for the batch in one query before the loop, reducing U SELECTs to 1.
• add_ioc() checks the cache first, falls back to the repo only on a miss, and updates the cache after every save.
• _add_fks() now builds an in-memory map from self.ioc_records instead of making extra DB calls for IOCs already processed.
• Tanner's manual local ioc_cache in _classify_attacks() is removed and replaced by the processor-level cache.

Related issues

Closes #1241

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).
• Chore (refactoring, dependency updates, CI/CD changes, code cleanup, docs-only changes).

Checklist

Formalities

• I have read and understood the rules about how to Contribute to this project.
• I chose an appropriate title for the pull request in the form: Enhancement: bulk prefetch IOCs before processing to eliminate per-IOC SELECT queries. Closes #1241
• My branch is based on develop.
• The pull request is for the branch develop.
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• I documented my code changes with docstrings and/or comments.
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• I have added tests for the feature/bug I solved.
• All the tests gave 0 errors.

GUI changes

No GUI changes in this PR.