fixes #19401; fixes #19402; rework Forward declaration and finalizer for ORC

[ringabout]

fixes #19401
fixes #19402

It is a draft because It's the solution I can think of for now. I'm going to examine it tomorrow. At least it works for #19401 and #19402 locally.

[ringabout]

It seems that at the time of magicsAfterOverloadResolution is called, the finalizer function is not transformed completely. By adding a wrapper around the finalizer function, we can ignore the incomplete function body and delay the analysis to later phases. Finally, when the finalizer function gets transformed properly, and the wrapper function will call it. So we don't need to touch the internal symbols of the finalizer function.

For instance

type
  Object = object
  Ref = ref Object

proc delete(x: Ref)

It generates a deleteFinalizerWrapper function:

proc delete(x: Ref)
proc deleteFinalizerWrapper(x: var Object) =
  delete(x)

After some refactorings, it can solve #19231 too

[github-actions]

Thanks for your hard work on this PR!
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Hint: mm: orc; threads: on; opt: speed; options: -d:release
164214 lines; 17.767s; 667.836MiB peakmem