Beeper MCP first-class connector + reposition channels admin

[lezama]

Problem

Beeper is a multi-network messaging client that exposes an official MCP server (listed at automattic.ai). An agent that connects to Beeper's MCP gets WhatsApp + Signal + iMessage + Telegram + Discord + Slack + Messenger + more through a single auth, instead of seven separate per-network integrations each with its own policy gate, token mint, and webhook plumbing.

For a generic chat-with-an-agent plugin, this is the highest leverage messaging integration in 2026: one connector, every conversation surface its user already lives in.

Scope

1. New first-class channel entry "Beeper" at the top of the channels wizard, above existing options. Single button "Connect your Beeper".
2. Reuses the MCP client bridge substrate from Bridge external MCP servers as built-in tools (Context7, Fetch, GitHub) #38 / PR MCP client: bridge external MCP servers as built-in tools (closes #38) #51 — Beeper is added as a built-in recipe in the bridged-MCP-servers admin, with the auth/token form pre-shaped for Beeper's MCP endpoint.
3. Channel adapter that maps Beeper's MCP message tools (send_message, list_recent_messages, etc.) to openclawp's canonical message shape used by class-openclawp-message-adapter.php — so an inbound Beeper message dispatches to the configured agent the same way WhatsApp/Telegram do.
4. Network filtering: per-Beeper-connection, user picks which underlying networks the agent should listen on (e.g. "only WhatsApp + Signal, ignore Telegram").
5. Reposition channels admin:
   • Beeper (new) — Connect once, reach the user wherever they are.
   • WhatsApp Cloud API — Official, requires Meta business verification.
   • Telegram Bot API — Free, simplest setup (#39).
   • External WhatsApp Gateway — For self-hosted evolution-api / wacli / baileys (#62).
6. Docs: docs/beeper-setup.md with the connect flow + per-network filtering recipe.

Acceptance criteria

• User pastes Beeper MCP token → connection succeeds → bridged-network picker shows the networks their account has set up.
• Message in any picked network reaches the configured agent within a few seconds.
• Reply goes back out via Beeper's MCP send_message and lands in the originating network.
• WhatsApp Cloud API, Telegram, and External Gateway channels continue to work unchanged.
• Channels admin shows the four options in the order specified above.
• HMAC / token auth follows Beeper's MCP server's documented method.

Notes

• Channel adapter follows the same shape contract as class-openclawp-whatsapp.php and the Telegram class in Telegram Bot API ingress channel #39 / PR Telegram: Bot API ingress channel (closes #39) #48 — anything new should be in the message-adapter layer, not duplicated.
• This is additive, not destructive. All three other messaging paths stay. The pivot is presentation order + a new recipe, not removal.
• Pairs with Bridge external MCP servers as built-in tools (Context7, Fetch, GitHub) #38 (MCP client bridge) — this issue depends on PR MCP client: bridge external MCP servers as built-in tools (closes #38) #51 landing first so the substrate exists.