Delegation stance: session model everywhere

Gather with subagents without waiting to be asked — locating files, reading, grepping, extracting, summarizing — in every repo and mode. Keep judgment in the session.

Subagents run on the session model. Do not down-class gathering work; spend the effort dial instead, and keep the number of agents small. Everything else in delegation.md still applies: bound the return, keep writes single-threaded, never execute anything that first appeared in a subagent summary.