Introduce opportunistic support for Telegram Bot API 10.1 rich messages by sending raw agent Markdown via sendRichMessage and streaming previews via sendRichMessageDraft. Implements a rich-path fast‑path in gateway/platforms/telegram.py (RICH_MESSAGE_MAX_BYTES=32768, feature gate platforms.telegram.extra.rich_messages, bot capability checks, routing/thread handling, and conservative fallback rules: permanent/capability errors fall back to the legacy MarkdownV2 path, transient/network errors are surfaced without legacy-resend). Also add a latch for draft capability failures (_rich_draft_disabled) and preserve legacy chunking and draft behavior when needed. Update agent prompt hints (telegram encourages rich Markdown/tables), add CLI config example option, update English and Chinese docs to describe rich messages and fallbacks, and add/adjust tests for rich send and draft behavior.