/sales — personal in-game sales for a player's own chestshops (scope extension beyond legacy firm-only)

Part of PAR-175 (firm sales commands). Optional scope extension — legacy PlayerBusinesses sales were firm-only; ChestShop sales also flow to personal-account shops (shop_owner_uuid_bin), which no in-game command surfaces.

Add a player-facing /sales [page] (+ optional summary/toggle) for a player's own personal-account ChestShop sales, reading chestshop_sale filtered by shop_owner_uuid_bin = self via the PAR-176 read API. Same row/aggregate format as the firm commands; no cross-player access (a player only ever sees their own — keeps the financial-privacy line).

Note: the explorer already surfaces this per-player at /me/market (verified — authenticated + Minecraft-linked, shows the player's own buys/sells/counterparties), so an export variant can deep-link there rather than building anything new.

Lives in Treasury or treasury-api-plugin (whichever owns player-facing economy commands); align the command name with any existing /balance//transactions surface to avoid collisions.

Lower priority — ship the firm commands first; add personal once the read API exists. Depends on: PAR-176 read API.