Add POST /webhook/{groupId} with per-group secrets (KV tenant:{groupId}), a custom provider (X-WebHooker-Signature HMAC, arbitrary JSON -> custom events through the route pipeline), and GitHub App installation isolation (Group.installationId) with automatic provisioning on installation.created (inst-{id} groups or binding matching owners groups). Includes WebhookPanel admin UI, custom route template, docs and 157 passing tests.
Add an optional Discord channel/thread or Telegram chat/topic (Group.logTarget) that receives a summary message per webhook the group's routes dispatched: event/action, repo, delivery id and per route×target OK/FAIL lines with green/red embed color. Validated by the admin API and editable in the group editor; docs and example config updated.
Route.lang is removed; Group.lang now drives the message language for
every route in the group (default en, custom via KV i18n:<lang>).
dispatch.ts loads translations per group and falls back to en for
groups without a lang. Admin UI: GroupEditor gains the language field,
RouteEditor/RouteCard drop theirs; docs and config example updated.
