refactor: streamline tag filtering logic in SpecFilter

[Mattias-Sehlstedt]

Pull Request

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Description

Introduced an object (TagFilter) to couple the Tag filtering fields to each other. it also breaks out the filtering logic into a private support method. This is part of making the behavior more understandable with the intent of making the necessary changes needed for the OAS 3.2 Tag functionality easier to integrate. Mainly the pruning of filtered Tags that are involved with the new parent field (i.e., if the parent is removed as part of the regular filtering, then the children should no longer refer to it).

This change is extracted from the Tag implementation present on branch.

Type of Change

• 🐛 Bug fix
• ✨ New feature
• ♻️ Refactor (non-breaking change)
• 🧪 Tests
• 📝 Documentation
• 🧹 Chore (build or tooling)

Checklist

• I have added/updated tests as needed
• I have added/updated documentation where applicable
• The PR title is descriptive
• The code builds and passes tests locally
• I have linked related issues (if any)

Screenshots / Additional Context