fix: Address remaining PR review comments

- Update regex pattern to support multi-word attribute names (e.g., 'aspect ratio')
- Rename $includeDeleted to $matchDeleted for clarity (matches deleted flag value)
- Add check to skip attributes not in caller-provided definitionIds filter
- Use Unicode pattern modifier 'u' for international character support in attribute names

This addresses CodeRabbit's feedback on PR #4442.
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