Preserve resumable state-machine lowering in Debug

[majocha]

Fixes #20466

Debug compilation could route inline builders containing low-level resumable state machines through generated helper methods. That helper boundary hid nested ResumableCode definitions from lowering, causing incorrect execution for composed builders such as TaskSeq. Keep resumable inline expansions in the caller's expression tree while preserving the existing helper specialization for ordinary inline methods.

[github-actions]

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`src/Compiler`	docs/release-notes/.FSharp.Compiler.Service/11.0.100.md	No current pull request URL (#20469) found, please consider adding it

[majocha]

The idea is to preserve the exact behavior of from before #19548. Resumable code lowers to static branch whenever possible even in debug.

[majocha]

This is AI generated and clearly fails regression tests.
The gist of the problem is forcing a resumable state machine that for whatever reason has no dynamic implementation into dynamic path. This is a breaking change at least wrt debugging.

[T-Gro]

This is a breaking change at least wrt debugging.

This is a break we can take in order to make the fix.
That way, we at least motivate people to test runtime async sooner :)