templates/macros use no expected types when return types are specified

[ringabout]

fixes #24296
fixes #24295

Templates use expectedType for type inference. It's justified that when templates don't have an actual return type, i.e., untyped etc.

When the return type of templates is specified, we should not infer the type

template g(): string = ""

let c: cstring = g()

In this example, it is not reasonable to annotate the templates expression with the cstring type before the fitNode check with its specified return type.

[ringabout]

It seems to break templates that present int literals:

Before my PR, the type inference seemed to treat int literals differently:

block: # bug #24295
  template g(_: int): int = 12
  proc foo(x: uint, y: uint) =
    echo (x, y)

  let c: uint = 0.g() # type mismatch: got 'uint' for '12' but expected 'int'
  foo(12, g(0)) # compiles

block:
  proc foe(): int = 12
  proc foo(x: uint, y: uint) =
    echo (x, y)
  let c: uint = foe() # type mismatch: got 'int' for 'foe()' but expected 'uint'
  foo(12, foe()) # type mismatch: got 'int' for 'foe()' but expected 'uint'

[ringabout]

It seems that in old Nim versions, templates just inline expressions without annotating the int literals with types

[github-actions]

Thanks for your hard work on this PR!
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Hint: mm: orc; opt: speed; options: -d:release
175125 lines; 8.410s; 655.227MiB peakmem