Enable the Enhanced Security Capability

The [Enhanced Security](https://developer.apple.com/documentation/Xcode/enabling-enhanced-security-for-your-app) capability enables a set of features that makes your app more secure. Especially notable is Apple's [Memory Integrity Enforcement](https://security.apple.com/blog/memory-integrity-enforcement/), a feature that protects against memory safety bugs. Enabling this feature would give iSH a huge security boost using just built-in security features of Xcode and iOS.

Review the linked Apple Enhanced Security documentation and the iSH Xcode project settings first. Confirm that the capability is compatible with iSH's iOS target; done means the capability is enabled and the app builds and runs with the security feature active.

Written by the indexing model from the issue text.