Reconsider internal agent-ops documents tracked at the repo root

[div0-space]

Raised in PR #69 review (pending thread r3737394711): "It is doubtful whether such assets should be included as root-level documents in a public repository."

The repository is public, and the root currently tracks documents whose audience is the internal agent fleet, not users or contributors:

• AGENT_BUS.md — live cross-agent signal bus (operator-away markers, UI divergence audit signals, internal wake-up protocol). Operational state, not documentation.
• .commitmsg — internal commit-message template for the agent fleet.
• AGENTS.md — canonical per-repo agent instructions. This one is a deliberate convention (agent-agnostic instruction file), but its new swarm/fast-boot sections lean operational; worth deciding how much belongs in a public surface.

Questions to settle:

1. Which of these carry information that should not be public (internal paths, operational signals, fleet topology)?
2. Should AGENT_BUS.md move to an ignored location (e.g. ~/.vibecrafted/ or a gitignored .vibecrafted/ dir) with only the protocol description staying tracked?
3. Is .commitmsg needed in-tree at all, or can the commit template live in hooks/tooling config?

Acceptance: an explicit decision per file (keep public / move / strip), applied consistently, with .gitignore fencing where applicable.