feat(bots): refine event binding editor UI and i18n

- Move conditions toggle between event select and arrow; drop "IF" label
- Remove "all events" (*) option from event select
- Add i18n labels for concrete event names (zh/en/ja) via bots.eventNames
- Narrow fallback event set to message.received for adapters without
  declared supported_events (legacy adapters only emit message.received)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

web/src/i18n/locales/en-US.ts

@@ -388,6 +388,23 @@ const enUS = {
     eventCustom: 'Custom event',
     eventWildcard: 'All events',
     eventNamespaceWildcard: '{{namespace}}.*',
+    eventNames: {
+      message_received: 'Message received',
+      message_edited: 'Message edited',
+      message_deleted: 'Message deleted',
+      message_reaction: 'Message reaction',
+      feedback_received: 'Feedback received',
+      friend_request_received: 'Friend request received',
+      friend_added: 'Friend added',
+      group_member_joined: 'Member joined group',
+      group_member_left: 'Member left group',
+      group_member_banned: 'Member banned',
+      bot_invited_to_group: 'Bot invited to group',
+      bot_removed_from_group: 'Bot removed from group',
+      bot_muted: 'Bot muted',
+      bot_unmuted: 'Bot unmuted',
+      platform_specific: 'Platform-specific event',
+    },
     conditions: 'Conditions',
     conditionsDescription:
       'All conditions must match to trigger this binding. Leave empty to always trigger.',