Added conversion to and from bounded int guarantee.

[orizi]

Summary

---

Type of change

Please check one:

• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

⚠️ Note:
To keep maintainer workload sustainable, we generally do not accept PRs that
are only minor wording, grammar, formatting, or style changes.
Such PRs may be closed without detailed review.

---

Why is this change needed?

---

What was the behavior or documentation before?

---

What is the behavior or documentation after?

---

Related issue or discussion (if any)

---

Additional context

[reviewable-StarkWare]

This change is 

[orizi]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• WIP: updates. #10181
• Added new guarantee split libfunc. #10180
• Changed u128_to_u32_guarantees input to be guarantee as well. #10179
• Added conversion to and from bounded int guarantee. #10178 👈 (View in Graphite)
• Added suppport for u128 guarantee in bounded_int_guarantee_verify. #10177
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.