docs(telegram): recommend allowlist for single-user DM policy (openclaw#34841)

* docs(telegram): recommend allowlist for single-user bots

* docs(telegram): condense single-user allowlist note

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Co-authored-by: echoVic <echovic@163.com>

Author: echoVic

docs/channels/telegram.md

@@ -119,6 +119,8 @@ Token resolution order is account-aware. In practice, config values win over env
     If you upgraded and your config contains `@username` allowlist entries, run `openclaw doctor --fix` to resolve them (best-effort; requires a Telegram bot token).
     If you previously relied on pairing-store allowlist files, `openclaw doctor --fix` can recover entries into `channels.telegram.allowFrom` in allowlist flows (for example when `dmPolicy: "allowlist"` has no explicit IDs yet).
 
+    For one-owner bots, prefer `dmPolicy: "allowlist"` with explicit numeric `allowFrom` IDs to keep access policy durable in config (instead of depending on previous pairing approvals).
+
     ### Finding your Telegram user ID
 
     Safer (no third-party bot):