persona packs after #1846: what's the intended path for headless / self-hosted seats?

## Context

I run a self-hosted relay with several persona agents as standalone buzz-acp seats on a
VPS. No desktop in the loop at runtime. The desktop connects as a client, but the seats
live on the server so they stay up when my laptop doesn't.

I authored the team as a persona pack against PERSONA_PACK_SPEC.md. `buzz pack validate`
passes. Then I went looking for what consumes it and found the history instead: #297
added `--persona-pack` / `--persona-name` to the ACP harness in April, and #1846 removed
them in July as part of unifying the team model around `TeamRecord` and snapshots. Today
`buzz-persona` sits in buzz-acp's Cargo.toml unimported, and the spec still describes
buzz-acp as the component that loads packs (sections 6, 10, 12, and the PF table).

So I can't tell if I'm looking at a gap or a decision.

## Question

For agents that run as headless buzz-acp seats on a server, what's the intended way to
give them a persona, skills, and behavioral config going forward?

1. If the answer is "TeamRecord + snapshots, packs are desktop-authoring only": is there
a planned path for snapshots to reach a headless seat (import via CLI, or the relay)?
And should the spec drop or rewrite the buzz-acp sections so it stops describing the
removed integration?
2. If a headless pack path is still wanted post-#1846: I'm happy to build it and carry it
through review. Roughly `--pack ` + `--persona ` on buzz-acp, resolved
through the existing buzz-persona resolver, persona prompt into the existing
`[System]` block, skills copied to `$AGENT_CWD/.agents/skills/` per the spec's
no-overwrite rule. One persona per process, matching how seats already run. But I
didn't want to open that PR against a direction you deliberately moved away from
two weeks ago.

## What I do today

A sync script that flattens each persona into the agent runtime's own config (prompt
file, skills dir, one seat env per agent). Works fine. It just re-implements the
deploy-time steps the spec assigns to buzz-acp, which is why I'm asking rather than
assuming.

Related: #2773 (BYOH, which these seats effectively are), #2958 (marketplace RFC leans
on portable personas), #2340 (open examples pack). Closest to a duplicate I found is
#3277 (managed agents only mentionable from the machine that runs them), which is
adjacent but about mentions, not persona delivery. Happy to close this if the plan is
already written down somewhere I missed.