Fix for subroutine + for loop + qubit allocation

[paul0403]

Context:
Subroutine + for loop + qubit allocation fails.
This is because there's an integer check when judging whether a wire label was dynamically allocated or not. This logic fails because subroutines take in all wire labels as subroutine arguments, hence they are tracers.

Description of the Change:
Relocate the check to only where it's needed (as a throwback to relay truly const dynamically allocated wire indices, so subscope handlers can remove them from their subjaxpr's consts).

Benefits:
Subroutine + for loop + qubit allocation works. This unblocks decomp rules with dynamic allocation.

Related GitHub Issues: fixes #2263

[sc-105198]

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.57%. Comparing base (134f086) to head (582e556).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2268   +/-   ##
=======================================
  Coverage   97.57%   97.57%           
=======================================
  Files          93       93           
  Lines       11245    11248    +3     
  Branches     1076     1078    +2     
=======================================
+ Hits        10972    10975    +3     
  Misses        208      208           
  Partials       65       65           

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