Atomically claim the next claimable task (dependency-aware)

Runs inside a BEGIN IMMEDIATE transaction (SQLite serialises writers) and claims the lowest-id task that is unowned, pending, and has no unfinished blocker (all its deps blockers are done). With no deps this is exactly the old FIFO claim (backward compatible). Returns NULL when nothing is currently claimable – which may mean "all done" OR "remaining tasks are still blocked", so a worker should back off and retry rather than exit (see team_coordinate).

Usage

board_claim(db_path, worker_id)

Arguments

db_path

Character. Board path.

worker_id

Character. Identifier for the claiming worker.

Value

A one-row data.frame (id, prompt) for the claimed task, or NULL.