Add --no-preview flag to send text

[dapi]

Problem

When sending messages with inline links via tgcli send text --parse-mode markdown, Telegram generates a link preview (URL embed) automatically. There is no way to disable this.

Proposed solution

Add --no-preview boolean flag to send text command to disable automatic link preview.

tgcli send text --to <id> --message "Check [this](https://example.com)" --parse-mode markdown --no-preview

MTProto mapping: messages.sendMessage → noWebpage: true

Note: send file with caption can also contain links, but Telegram does not generate link previews for media messages — only for plain text. So --no-preview applies to send text only.

Implementation plan

1. cli.js: add --no-preview boolean option to send text command
2. telegram-client.js → sendTextMessage(): pass noWebpage: true in params when flag is set
3. mcp-server.js: add no_preview boolean parameter to sendMessage MCP tool
4. docs/cli.md: document the new flag
5. SKILL.md: update Send Text section with --no-preview examples

gramjs verification: confirm that client.sendText(peer, text, { noWebpage: true }) is supported — check gramjs sendMessage params interface.

Context

Telegram MTProto API supports noWebpage parameter in messages.sendMessage. This is especially useful for digest-style posts with multiple links where preview clutters the message.

See also: #11 (other missing send parameters: --silent, --no-forwards, --caption-above, --spoiler, --schedule, --force-document)

Current workaround

Use telegram-mcp send_message with disable_web_page_preview: true, but this breaks the workflow when everything else is done via tgcli.

Acceptance criteria

• tgcli send text --no-preview sends message with noWebpage: true
• MCP sendMessage tool accepts no_preview parameter
• Documented in docs/cli.md
• SKILL.md updated (Send Text section with --no-preview example)
• Smoke tested: message with link sent without preview