* docs: add WeChat channel via official Tencent iLink Bot plugin
Add WeChat to the README channel lists and setup section.
Uses the official Tencent-published plugin @tencent-weixin/openclaw-weixin
which connects via the iLink Bot API (QR code login, long-poll).
Requires WeChat 8.0.70+ with the ClawBot plugin enabled; the plugin
is being rolled out gradually by Tencent.
Covers: setup steps, capabilities (DM-only, media up to 100 MB,
multi-account, pairing authorization, typing indicators, config path),
and the context token restart caveat.
* docs: update WeChat plugin install for v2.0 compatibility
- Add version compatibility note (v2.x requires OpenClaw >= 2026.3.22,
@legacy tag for older hosts)
- Add plugins.allow step (required since plugins.allow was introduced)
* docs: drop manual plugins.allow/enable steps (handled by plugins install)
* docs: fix multi-account instruction to require explicit --account id
* docs: trim WeChat section to match neighboring channels, fix pairing link
* docs: sync WeChat channel docs
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Co-authored-by: Ayaan Zaidi <hi@obviy.us>
