Fix commute-ppr pass to correctly handle PPR's operands across different blocks (#2267)

**Description of the Change:**
This update addresses an issue where the `commute_ppr` pass incorrectly
modified the operands of PPRs across different blocks or regions. The
logic has been modified to ensure that PPRs are only moved within the
same block.

[[sc-105282]]

Author: sengthai

doc/releases/changelog-dev.md

@@ -347,6 +347,11 @@
 
   This fix enables automatic qubit management to be used with gradients.
 
+
+* Fixed the :func:`~.passes.commute_ppr` pass incorrectly modifying operands of PPRs that live in
+  different blocks.
+  [(#2267)](https://github.com/PennyLaneAI/catalyst/pull/2267)
+
 * The `--inline-nested-module` pass no longer renames external function declarations.
   [(#2244)](https://github.com/PennyLaneAI/catalyst/pull/2244)
 

mlir/lib/QEC/Transforms/CommutePPR.cpp

@@ -132,7 +132,11 @@ void moveCliffordPastNonClifford(const PauliStringWrapper &lhsPauli,
 
     // Update the use of value in newRHSOperands
     for (unsigned i = 0; i < newRHSOperands.size(); i++) {
-        newRHSOperands[i].replaceAllUsesExcept(nonCliffordOp.getOutQubits()[i], nonCliffordOp);
+        newRHSOperands[i].replaceUsesWithIf(
+            nonCliffordOp.getOutQubits()[i], [&](OpOperand &operand) {
+                return operand.getOwner() != nonCliffordOp &&
+                       operand.getOwner()->getBlock() == lhs->getBlock();
+            });
     }
 
     rewriter.replaceOp(rhs, rhs.getInQubits());