Consolidate overlapped I/O non-Windows stubs; remove stale ILLink workaround; remove incorrect [RequiresUnsafe] annotations - #125507

Consolidate overlapped I/O non-Windows stubs; remove stale ILLink workaround; remove incorrect [RequiresUnsafe] annotations#125507

jkotas merged 31 commits into

maindotnet/runtime:mainfrom

copilot/remove-duplicate-overlapped-implementationsdotnet/runtime:copilot/remove-duplicate-overlapped-implementationsCopy head branch name to clipboard