Smarter Reduced Cost Spoke

[bknueven]

Minor changes to RC Spoke:

1. Make sure we send new nonant bounds as soon as they're calculated
2. If the Lagrangian subproblems don't result in a lower bound this time, we check for updates to the primal solution

[Copilot]

Pull Request Overview

This PR introduces changes to the Reduced Cost Spoke to ensure that new nonant bounds are sent immediately after they are calculated and to enable a check for updates to the primal solution when the Lagrangian subproblems do not lower the bound.

• In lagrangian, an else branch has been added to call extract_and_store_updated_nonant_bounds with new_dual set to false.
• In extract_and_store_updated_nonant_bounds, a call to update_nonant_bounds has been added, and the explicit update call in do_while_waiting_for_new_Ws has been removed.

Comments suppressed due to low confidence (3)

mpisppy/cylinders/reduced_costs_spoke.py:143

• [nitpick] Consider adding an inline comment explaining why the branch sets new_dual to false, especially compared to the new_dual=true branch above.

            self.extract_and_store_updated_nonant_bounds(new_dual=False)

mpisppy/cylinders/reduced_costs_spoke.py:356

• [nitpick] Ensure that removing the redundant update_nonant_bounds call in do_while_waiting_for_new_Ws does not omit any critical updates in edge cases.

        self.extract_and_store_updated_nonant_bounds(new_dual=False)

mpisppy/cylinders/reduced_costs_spoke.py:322

• [nitpick] Verify that moving the update_nonant_bounds call inside extract_and_store_updated_nonant_bounds maintains the intended update order in all scenarios.

        self.update_nonant_bounds()