- Add spawn_in_process_agent() to SwarmCoordinator: creates lightweight
SwarmNode instances that share the coordinator's comms layer and
AuctionManager, enabling synchronous bid submission
- Fix post_task() to open the auction BEFORE announcing via comms so
in-process agent callbacks can submit bids into an open auction
- Fix run_auction_and_assign() to close an already-open auction instead
of re-opening (which would discard bids)
- Add POST /swarm/tasks/auction route for atomic task+auction flow
- Add 7 integration tests (TDD) covering the full lifecycle:
spawn → post → auction → assign → complete