feat(telegram,discord): permission-relay capability + bidirectional handlers

Complete the plugin side of anthropics/claude-cli-internal#23061 (permission
prompts over channels).

Capability: both servers now declare
  experimental["claude/channel/permission"]
which tells CC they can relay permission requests. This capability asserts the
server authenticates the replier — gate()/access.allowFrom filters
non-allowlisted senders before handleInbound runs.

Outbound (CC → user): setNotificationHandler for
  notifications/claude/channel/permission_request
formats the tool name, description, and input preview into a human-readable
message and sends it to every allowlisted DM. Groups are excluded — the
security thread resolution was "single-user mode for official plugins."

Inbound (user → CC): PERMISSION_REPLY_RE intercept in handleInbound catches
"yes xxxxx" / "no xxxxx" replies, emits the structured
  notifications/claude/channel/permission
event with {request_id, behavior}, reacts with checkmark/cross, and returns
without relaying the text to Claude as a chat message.

The regex is inlined from channelPermissions.ts (no cross-repo dep). IDs are
lowercased at the plugin boundary per the case-insensitive spec.

Version bumped 0.0.1 → 0.0.2 so the plugin reconciler picks up the change.

🏠 Remote-Dev: homespace

external_plugins/discord/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "discord",
   "description": "Discord channel for Claude Code \u2014 messaging bridge with built-in access control. Manage pairing, allowlists, and policy via /discord:access.",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "keywords": [
     "discord",
     "messaging",