feat(telegram): add silent message option (#2382)

* feat(telegram): add silent message option (disable_notification)

Add support for sending Telegram messages silently without notification
sound via the `silent` parameter on the message tool.

Changes:
- Add `silent` boolean to message tool schema
- Extract and pass `silent` through telegram plugin
- Add `disable_notification: true` to Telegram API calls
- Add `--silent` flag to CLI `message send` command
- Add unit test for silent flag

Closes #2249

AI-assisted (Claude) - fully tested with unit tests + manual Telegram testing

* feat(telegram): add silent send option (#2382) (thanks @Suksham-sharma)

---------

Co-authored-by: Pocket Clawd <pocket@Pockets-Mac-mini.local>

CHANGELOG.md

@@ -41,6 +41,7 @@ Status: unreleased.
 - Routing: precompile session key regexes. (#1697) Thanks @Ray0907.
 - TUI: avoid width overflow when rendering selection lists. (#1686) Thanks @mossein.
 - Telegram: keep topic IDs in restart sentinel notifications. (#1807) Thanks @hsrvc.
+- Telegram: add optional silent send flag (disable notifications). (#2382) Thanks @Suksham-sharma.
 - Config: apply config.env before ${VAR} substitution. (#1813) Thanks @spanishflu-est1918.
 - Slack: clear ack reaction after streamed replies. (#2044) Thanks @fancyboi999.
 - macOS: keep custom SSH usernames in remote target. (#2046) Thanks @algal.