Decomposing 15 Tasks Across 3 Teammates Without File Conflicts

You're using an agent team to add structured logging to a service. The work breaks down into 15 roughly similar tasks: adding a log statement to each of 15 handler functions spread across 6 files (orders.ts has 4 handlers, users.ts has 3, payments.ts has 3, inventory.ts has 2, shipping.ts has 2, refunds.ts has 1). You plan to spawn 3 teammates.

1. Explain why naively splitting "15 tasks / 3 teammates = 5 tasks each" without regard to which file each task touches is a bad decomposition here, referencing what agent teams do (and don't do) to protect against the risk this creates.
2. Propose a concrete task assignment across the 3 teammates and the 6 files that avoids that risk, and explain the principle behind your assignment.
3. One of your handler functions in orders.ts needs a shared logging helper to exist first, and you want the teammate who creates that helper to finish before any other orders.ts handler tasks start. Explain how you'd express and enforce that ordering using the mechanisms this subject covers, rather than just hoping the teammates coordinate it themselves informally.