- Removed the sticky category-chip row from /diy (sections still group the cards).
- New in-app tool at /diy/deck-cost (components/DeckCostCalculator.tsx): a
self-contained pricing model — labour rate + overhead, equipment amortisation,
operation expenses, materials (with order/unload time), process time,
packaging, profit margin and scrap → cost per board and a fair selling price
(no-packaging / with-packaging). State persists to localStorage; reset to the
worked example. The "Deck cost & pricing" card now links to it instead of
showing "Coming soon".
- Smoke test walks /diy/deck-cost.
