[deep-sengupta]

Summary

• Handle scanner findings that do not provide a CredData rule name.
• Avoid creating invalid metadata rows with an empty category.
• Preserve existing rule-based matching behavior.
• Add regression tests for rule-less detections, missing metadata, duplicate findings, and existing rule-based matching.

Problem

Some scanner adapters pass a file path and line number to check_line_from_meta() without providing a rule name. The method can attempt to create a MetaRow with an empty Category, which may raise a ValueError.

Solution

Handle rule-less detections explicitly and defer metadata-row creation until it is needed. Keep metadata validation unchanged, define consistent matching and counting behavior for findings without rule names, and use a non-empty fallback category when saving new metadata in fix mode.

Testing

• Rule-less scanner regression tests pass.
• Existing unit tests pass.
• Rule-based matching behavior remains unchanged.
• git diff --check passes.