iOS developers can produce smaller apps when targeting .NET6

[marek-safar]

This is a tracking issue for all cross teamwork to deliver the same or better app size for Xamarin iOS/tvOS Xamarin apps migrating to .NET6

Goals

• Same or smaller size SingleView app for release arm64 output (less than 4.35 MB)
• Same or smaller size default MAUI app template for iOS than Xamarin.Forms (TBD)

Work Items

• Core Managed libraries size reduction on top of Core Managed libraries size-reduction for WebAssembly #44530
  • System.Net.Quic is not trimmed on mobile platforms #46915
• iOS-specific size reduction work .NET: SingleView app size macios#10249
• MAUI-specific size reduction work
• Enable size tracking testing infrastructure for netcore
  • Add size tracking for iOS functional tests
  • Add size tracking for Xamarin iOS sample
  • Add size tracking for MAUI iOS sample
• [mono] Tracking: iOS - Size reduction #61815