iMessage: promote BlueBubbles and refresh docs/skills (#8415)

* feat: Make BlueBubbles the primary iMessage integration

- Remove old imsg skill (skills/imsg/SKILL.md)
- Create new BlueBubbles skill (skills/bluebubbles/SKILL.md) with message tool examples
- Add keep-alive script documentation for VM/headless setups to docs/channels/bluebubbles.md
  - AppleScript that pokes Messages.app every 5 minutes
  - LaunchAgent configuration for automatic execution
  - Prevents Messages.app from going idle in VM environments
- Update all documentation to prioritize BlueBubbles over legacy imsg:
  - Mark imsg channel as legacy throughout docs
  - Update README.md channel lists
  - Update wizard, hubs, pairing, and index docs
  - Update FAQ to recommend BlueBubbles for iMessage
  - Update RPC docs to note imsg as legacy pattern
  - Update Chinese documentation (zh-CN)
- Replace imsg examples with generic macOS skill examples where appropriate

BlueBubbles is now the recommended first-class iMessage integration,
with the legacy imsg integration marked for potential future removal.

* refactor: Update import paths and improve code formatting

- Adjusted import paths in session-status-tool.ts, whatsapp-heartbeat.ts, and heartbeat-runner.ts for consistency.
- Reformatted code for better readability by aligning and grouping related imports and function parameters.
- Enhanced error messages and conditional checks for clarity in heartbeat-runner.ts.

* skills: restore imsg skill and align bluebubbles skill

* docs: update FAQ for clarity and formatting

- Adjusted the formatting of the FAQ section to ensure consistent bullet point alignment.
- No content changes were made, only formatting improvements for better readability.

* style: oxfmt touched files

* fix: preserve BlueBubbles developer reference (#8415) (thanks @tyler6204)

README.md

@@ -120,7 +120,7 @@ Run `openclaw doctor` to surface risky/misconfigured DM policies.
 ## Highlights
 
 - **[Local-first Gateway](https://docs.openclaw.ai/gateway)** — single control plane for sessions, channels, tools, and events.
-- **[Multi-channel inbox](https://docs.openclaw.ai/channels)** — WhatsApp, Telegram, Slack, Discord, Google Chat, Signal, iMessage, BlueBubbles, Microsoft Teams, Matrix, Zalo, Zalo Personal, WebChat, macOS, iOS/Android.
+- **[Multi-channel inbox](https://docs.openclaw.ai/channels)** — WhatsApp, Telegram, Slack, Discord, Google Chat, Signal, BlueBubbles (iMessage), iMessage (legacy), Microsoft Teams, Matrix, Zalo, Zalo Personal, WebChat, macOS, iOS/Android.
 - **[Multi-agent routing](https://docs.openclaw.ai/gateway/configuration)** — route inbound channels/accounts/peers to isolated agents (workspaces + per-agent sessions).
 - **[Voice Wake](https://docs.openclaw.ai/nodes/voicewake) + [Talk Mode](https://docs.openclaw.ai/nodes/talk)** — always-on speech for macOS/iOS/Android with ElevenLabs.
 - **[Live Canvas](https://docs.openclaw.ai/platforms/mac/canvas)** — agent-driven visual workspace with [A2UI](https://docs.openclaw.ai/platforms/mac/canvas#canvas-a2ui).
@@ -144,7 +144,7 @@ Run `openclaw doctor` to surface risky/misconfigured DM policies.
 
 ### Channels
 
-- [Channels](https://docs.openclaw.ai/channels): [WhatsApp](https://docs.openclaw.ai/channels/whatsapp) (Baileys), [Telegram](https://docs.openclaw.ai/channels/telegram) (grammY), [Slack](https://docs.openclaw.ai/channels/slack) (Bolt), [Discord](https://docs.openclaw.ai/channels/discord) (discord.js), [Google Chat](https://docs.openclaw.ai/channels/googlechat) (Chat API), [Signal](https://docs.openclaw.ai/channels/signal) (signal-cli), [iMessage](https://docs.openclaw.ai/channels/imessage) (imsg), [BlueBubbles](https://docs.openclaw.ai/channels/bluebubbles) (extension), [Microsoft Teams](https://docs.openclaw.ai/channels/msteams) (extension), [Matrix](https://docs.openclaw.ai/channels/matrix) (extension), [Zalo](https://docs.openclaw.ai/channels/zalo) (extension), [Zalo Personal](https://docs.openclaw.ai/channels/zalouser) (extension), [WebChat](https://docs.openclaw.ai/web/webchat).
+- [Channels](https://docs.openclaw.ai/channels): [WhatsApp](https://docs.openclaw.ai/channels/whatsapp) (Baileys), [Telegram](https://docs.openclaw.ai/channels/telegram) (grammY), [Slack](https://docs.openclaw.ai/channels/slack) (Bolt), [Discord](https://docs.openclaw.ai/channels/discord) (discord.js), [Google Chat](https://docs.openclaw.ai/channels/googlechat) (Chat API), [Signal](https://docs.openclaw.ai/channels/signal) (signal-cli), [BlueBubbles](https://docs.openclaw.ai/channels/bluebubbles) (iMessage, recommended), [iMessage](https://docs.openclaw.ai/channels/imessage) (legacy imsg), [Microsoft Teams](https://docs.openclaw.ai/channels/msteams) (extension), [Matrix](https://docs.openclaw.ai/channels/matrix) (extension), [Zalo](https://docs.openclaw.ai/channels/zalo) (extension), [Zalo Personal](https://docs.openclaw.ai/channels/zalouser) (extension), [WebChat](https://docs.openclaw.ai/web/webchat).
 - [Group routing](https://docs.openclaw.ai/concepts/group-messages): mention gating, reply tags, per-channel chunking and routing. Channel rules: [Channels](https://docs.openclaw.ai/channels).
 
 ### Apps + nodes
@@ -375,9 +375,15 @@ Details: [Security guide](https://docs.openclaw.ai/gateway/security) · [Docker
 
 - Requires `signal-cli` and a `channels.signal` config section.
 
-### [iMessage](https://docs.openclaw.ai/channels/imessage)
+### [BlueBubbles (iMessage)](https://docs.openclaw.ai/channels/bluebubbles)
 
-- macOS only; Messages must be signed in.
+- **Recommended** iMessage integration.
+- Configure `channels.bluebubbles.serverUrl` + `channels.bluebubbles.password` and a webhook (`channels.bluebubbles.webhookPath`).
+- The BlueBubbles server runs on macOS; the Gateway can run on macOS or elsewhere.
+
+### [iMessage (legacy)](https://docs.openclaw.ai/channels/imessage)
+
+- Legacy macOS-only integration via `imsg` (Messages must be signed in).
 - If `channels.imessage.groups` is set, it becomes a group allowlist; include `"*"` to allow all.
 
 ### [Microsoft Teams](https://docs.openclaw.ai/channels/msteams)