cloud(improvement): MCP announcement card (#4746)

## Description

Announcement cards + removed old announces

<img width="493" height="350" alt="Screenshot 2026-08-14 at 16 59 46"
src="https://github.com/user-attachments/assets/4867d83c-8248-4cc5-ba41-05948e0285af"
/>
<img width="473" height="450" alt="Screenshot 2026-08-14 at 16 59 36"
src="https://github.com/user-attachments/assets/88d8c39b-07be-4152-8c78-649ed196ca3a"
/>

## Release note

<!-- User-facing release note. Use "None" if this does not need release
notes. -->
None.

## Migration note

<!-- Upgrade, deployment, config, schema, or compatibility notes. Use
"None" if none. -->
None.

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