Add Telegram and Discord IM channels

plugin-src/host/rpc-authority.mjs

@@ -0,0 +1,11 @@
+const RPC_AUTHORITIES = new Set(['loopback', 'trusted-host']);
+
+/**
+ * Resolve the browser authority accepted by an IM management RPC channel.
+ * The default keeps credential and bot-management operations on loopback.
+ */
+export function resolveRpcAuthority(value) {
+  if (value === undefined) return 'loopback';
+  if (RPC_AUTHORITIES.has(value)) return value;
+  throw new TypeError('dsh-im rpcAuthority must be "loopback" or "trusted-host"');
+}