249aafdb0f
One process-global intern pool (intern_port/cost_port, the COL_PORTS LazyLock pattern) in the cost module is now the single source of the cost[k].<port>/cost[k].<field> names; CostSum::builder and cost_graph consume it and the per-build .leak()s in cost_graph are gone — the prerequisite before cost is rebuilt per member across a sweep. Two unit pins (same pointer for the same pair, dedup for bare names). Verified: aura-std 166/0, cost_graph 4/4, zero .leak() in the two sites, full workspace suite green, clippy -D warnings clean. closes #152 refs #234