Adding overflow/underflow protection in release mode

[ferencdg]

In release build we will now have runtime checks whether integers overflow or underflow. By doing so, one of the most common smart contract security weaknesses are prevented.

issue: Guard against overflows on balances [ch23813]

[shortcut-integration[bot]]

This pull request has been linked to Clubhouse Story #23813: Guard against overflows on balances.

[coveralls]

Pull Request Test Coverage Report for Build 1205866929

• 6 of 9 (66.67%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 31.888%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
xtc/src/lib.rs	6	9	66.67%
<!--	Total:	6	9	66.67%	-->

Totals
Change from base Build 1202066438:	0.1%
Covered Lines:	743
Relevant Lines:	2330

---

💛 - Coveralls