docs: align commit co-author policy (#388)

Align the repository and contributor rules with the maintainer credit policy while keeping external and upstream work trailer-free.

Co-authored-by: Codex <codex@openai.com>

Author: solomonneas

AGENTS.md

@@ -63,7 +63,7 @@ Format: trigger, then the rule, then what to do instead.
 - Bumping the version: update `pyproject.toml`, `src/brigade/__init__.py`, and
   every template `_brigade_version` field together. `./scripts/verify` checks
   the sync.
-- Committing: conventional commits, no co-authorship trailers.
+- Committing: use conventional commits. In escoffier-labs organizations and original solomonneas repositories, commits for substantial coding work should carry the coding agent's co-author trailer. External repositories and upstream third-party PRs remain trailer-free.
 
 ## Orientation
 

CONTRIBUTING.md

@@ -20,7 +20,7 @@ Brigade is the local-first operator CLI for agent memory, handoffs, and reviewab
 
 - Personal details, hostnames, IPs, account IDs, or live auth profiles in templates or tests. The whole point of this kit is to keep that stuff out of public repos. The `content-guard` job in CI will fail if it finds any.
 - Cron jobs or hooks that post or call out to the network without explicit opt-in.
-- AI-co-authorship trailers on commits (`Co-Authored-By: <model>`). Conventional commits only.
+- Commits must use conventional commits. In-house commits in escoffier-labs organizations and original solomonneas repositories should include a co-author trailer for a coding agent that did substantial work; external repositories and upstream third-party PRs remain trailer-free.
 
 ## Planning artifacts