[Team] Define the human, Chief and specialist authority contract #46

Planning ID: TODO-A

Related work: #39 / #45 delivered the general architecture documentation and are now closed/merged. This narrowly scoped follow-up defines the proposed multi-human ownership contract; coordinate the child-creation decision with #16.

Proposed PR title: docs: define team ownership and Chief collaboration boundaries.

Goal: make role and data-boundary decisions explicit before schema work.

Scope: document identity relationships, one designated Chief per pilot member, owner-scoped management, room visibility, approval authority and Chief-only cross-owner traffic. Include a routing matrix for human/Chief/specialist actors, ownership changes, and disabled/replaced Chiefs. Resolve whether specialists can create their own children within owner limits; do not leave #16 implicit.

Out of scope: implementation, social federation and general enterprise roles.

Dependencies: none.

Code area: architecture/subsystem docs introduced by #45; ownership invariants in the relevant contributing guidance.

Acceptance and tests: table-driven examples cover allowed same-owner delegation, allowed Chief-to-Chief requests, forbidden cross-owner specialist access, and the distinction between team administration and private owner authority. No route can turn another human’s request into owner approval by forwarding it.

Delivery

One focused implementation PR for this issue. This is planned work, not a claim of shipped multi-human support. Preserve the pristine upstream pin and generated patch/client boundaries. Keep team mode disabled until the documented authorization gates pass. Record exact tested head, executed checks, missing checks and independent review. No production credentials or live deployment are part of this issue.