Stop bind-mounting host ~/.claude into the agent container; auth via Meridian

[ivndev001]

Context

Cross-dev Claude credential leak — full root cause + locked Direction C in the developerz-ai/infrastructure incident doc: docs/incidents/2026-05-27-claude-cred-leak.md (see PR developerz-ai/infrastructure#49).

docs/docker.md runs the agent with -v ~/.claude:/home/claudetm/.claude:ro, mounting the host operator's ~/.claude (including the OAuth bearer token) into the container. That makes the agent run as whoever owns that token and bills their account.

Ask

• Remove the -v ~/.claude:... bind-mount.
• Authenticate the unattended agent through the central Claude proxy (Meridian) with a scoped, rotatable credential issued per consumer — never a human's Max token.

Acceptance

• No container mounts or reads a human's ~/.claude/.credentials.json.
• Agent auth is a scoped credential that can be rotated without touching anyone's personal Claude login.