Remove .NET 12 Mono runtime and cross-AOT packs #134397

Summary

Track removal of the selected .NET 12 Mono runtime and cross-AOT packs from the official build. Remove or replace dependencies on these packs in consumer repositories. Where Mono needs to remain, use pinned versions.

Tasks

• Remove or replace Mono dependencies and affected test configurations in consumer repositories.
  • dotnet/runtime
    • [PERF] Retire default Mono performance runs and builds on main #134602
    • [ci] Remove Mono coverage #135010
  • dotnet/sdk
    • Remove Mono packs from .NET 12 workloads sdk#56480
  • dotnet/aspnetcore
    • [ci] Use CoreCLR for WebAssembly trimming checks aspnetcore#69642
    • Remove Mono from the Components E2E pipeline aspnetcore#70440
  • dotnet/dotnet
    • Remove DotNetBuildUseMonoRuntime and Mono-only SDK build mode dotnet#10872
  • dotnet/android
    • net12.0 branch instead of main
    • [ci] Remove Mono coverage android#12973
  • dotnet/macios
    • net12.0 branch instead of main
    • Remove disabled Mono VM build and test paths macios#26689
  • dotnet/maui
    • net12.0 branch instead of main
    • [net12][ci] Remove Mono coverage maui#39052
  • dotnet/performance
    • need to keep net11 measurements alive for mono comparison
    • Add Mono performance opt-outs and remove SDK Mono invocations performance#5322
  • dotnet/BenchmarkDotNet
    • Reject unavailable .NET 12 Mono SDK toolchains BenchmarkDotNet#3278
  • dotnet/crank
    • Reject unavailable .NET 12 Mono runtime overrides crank#900
• Use pinned versions wherever Mono needs to remain.
• Open a VMR PR in dotnet/dotnet that removes the selected Mono runtime and cross-AOT packs.
  • Remove iOS and tvOS simulator x64 support for .NET 12 dotnet#10245
  • Exclude selected Mono runtime and cross-AOT packs from the VMR build dotnet#9909, draft.
  • Stop building Mono runtime and cross-AOT packs for DotNetBuildAllRuntimePacks #135100
• Merge the consumer and tooling PRs.
• Merge the VMR PR after the consumer and tooling PRs are merged.

VS/VSCode

Visual Studio and VS Code tooling changes are tracked separately.