Pull Request

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Description

Enhanced schema generation by recognizing

• @nullable annotations as nullable and adding "null" to the type array in OpenAPI 3.1.
• nullable = true in schema and adding "null" to the type array in OpenAPI 3.1.

Introduced a test case to validate the behavior and ensure backward compatibility with explicit @Schema annotations.

Fixes: #5001

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