Phase 179-A Step 4: Update TODO comment to be more specific about
the future improvement path (using MirBuilder's next_value_id()).
Changed vague "TODO: This should be delegated to a proper ValueId allocator"
to clear "Future improvement: Delegate to MirBuilder's next_value_id()".
Note: Other TODOs in loop_patterns/mod.rs are placeholder tests waiting
for future implementation and are intentionally kept as-is.
1e51c2c521