Tarkov-style flea market where users list locker items at a fixed price
and buyers pay through the banking system; items transfer directly
into the buyer's locker.
- market-listings + market-negotiations collections and the market page
with search/rarity filters and a Countdown timer on each card
- service lib (buyListing with partial-quantity + negotiated-price
support, clean-stock rule, creditLockerQuantity, auto pricing)
- negotiation flow: make/accept/reject/counter/withdraw, strictly-
increasing buyer offers, NPC vendor auto-resolution
- NPC vendors: game-npcs attribution, patience meter, dialogue, chat
bubbles, historical threads dialog
- 30d user / 7d auto listing durations, market-tick bin for expiry +
vendor restock, SSE notify on tick
- market event types + game-npcs/market target collections in the
event log; sidebar Market entry under Logistics
- partial-quantity purchases (buyListing/buyMarketListing/makeMarketOffer)
with full int test coverage (25 tests)
