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The ordering is the load-bearing part. All three changes interlock and every wrong interleaving fails silently: flipping the usage fallback to (0, 0) before the settlement points read the derived value refunds the whole pre-deduction on success, and flipping the embedding transport before _merge goes three-state mislabels unavailable batches as measured. So the plan adds the capability first, moves all five call sites onto it while it is still equivalent, only then lets the third state take effect, and unbinds the constraint last. Registers both wiki entries and links the plan to its design.