Stock Validation and Reservation

[DakotaCondos]

As the Order Service,
I want each bot to validate and reserve stock when accepting an order,
so that active and queued orders do not overcommit the bot’s inventory.

Acceptance Criteria

• Given a bot receives an order assignment
  When it checks stock availability
  Then it validates the order against available stock, not total stock.

• Given the bot has enough available stock
  When the order is accepted
  Then the bot immediately reserves the requested item quantities.

• Given the bot does not have enough available stock
  When the order is validated
  Then the bot rejects the order with an insufficient-stock response.

• Given stock is reserved for an accepted order
  When the reservation is created
  Then the bot generates a stock update event.

• Given a queued order has reserved stock
  When earlier deliveries are completed
  Then the queued order keeps its reservation until it is delivered or cancelled.

• Given an order is completed
  When delivery is finalized
  Then the reserved stock is converted into fulfilled stock and deducted from the bot’s onboard inventory.