docs: replace english locale mirrors with translated landing pages

docs/es/experiments/plans/group-policy-hardening.md

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----
-summary: "Telegram allowlist hardening: prefix + whitespace normalization"
-read_when:
-  - Reviewing historical Telegram allowlist changes
-title: "Telegram Allowlist Hardening"
----
-
-# Telegram Allowlist Hardening
-
-**Date**: 2026-01-05  
-**Status**: Complete  
-**PR**: #216
-
-## Summary
-
-Telegram allowlists now accept `telegram:` and `tg:` prefixes case-insensitively, and tolerate
-accidental whitespace. This aligns inbound allowlist checks with outbound send normalization.
-
-## What changed
-
-- Prefixes `telegram:` and `tg:` are treated the same (case-insensitive).
-- Allowlist entries are trimmed; empty entries are ignored.
-
-## Examples
-
-All of these are accepted for the same ID:
-
-- `telegram:123456`
-- `TG:123456`
-- `tg:123456`
-
-## Why it matters
-
-Copy/paste from logs or chat IDs often includes prefixes and whitespace. Normalizing avoids
-false negatives when deciding whether to respond in DMs or groups.
-
-## Related docs
-
-- [Group Chats](/concepts/groups)
-- [Telegram Provider](/channels/telegram)