✨ Stabilization of `Integer` type

[LVMVRQUXL]

📝 Description

Problem: The Integer type was introduced by #880 as an experimental declaration for representing an integer and solving related issues (like integer overflow when adding, subtracting or multiplying integers). Due to its stability stage, the solution provided by this type is only available by marking usages with an explicit opt-in annotation.

Solution: Stabilize the API of the Integer type introduced by #880.

✅ Checklist

See the Issue implementation section in the contributing guidelines before addressing the following checklist.

• [ ] ✨ Stabilize Integer type.
• [ ] 📝 Update unreleased changelog for this issue.