✨ Add QCO If operation

[li-mingbao]

Description

This PR adds the qco.if operation to the QCO dialect. This operation is similar to the scf.if operation but it takes an additional list of qubits as input that are passed down to the branches as block arguments. This is used in order to support linar typing for qubit values.

Example:

 %q2 = qco.if %condition qubits(%q0 : !qco.qubit) -> !qco.qubit {
    ^bb0(%arg0: !qco.qubit):
      %q1 = qco.h %arg0 : !qco.qubit -> !qco.qubit
      qco.yield %q1
    } else {
    ^bb0(%arg0: !qco.qubit):
      qco.yield %arg0
    }

Checklist:

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• I have added entries to the changelog for any noteworthy additions, changes, fixes, or removals.
• I have added migration instructions to the upgrade guide (if needed).
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the CI checks.
• I have reviewed my own code changes.

[codecov]

Codecov Report

❌ Patch coverage is 64.70588% with 42 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
mlir/lib/Dialect/QCO/IR/Scf/IfOp.cpp	54.8%	42 Missing ⚠️

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