Alt-Key on external keyboards do not work on iOS

**Describe the bug** When typing on an external keyboard, alt + key provides a different character (e.g. on my French keyboard, alt + A produces "æ", on a US keyboard alt +3 produces "#"). Currently, when typing on an external keyboard with SwiftTerm on iOS, alt + key produces nothing visible on screen (but it may have inserted invisible characters). **To Reproduce** - start an app using SwiftTerm on iOS - connect an external keyboard - type alt + 3 - nothing appears. **Expected behavior** I would expect the alternative characters to appear.