docs: update advanced-imessage-ts documentation for v2.1.0

[photon-action-bot]

Documentation Update: advanced-imessage-ts v2.1.0

This PR updates documentation for advanced-imessage-ts based on the v2.1.0 release.

Release Notes

New Features

• Inbound messages can now include decoded mini-app content, including app identity, session details, URL, live status, and visible layout text. This makes received iMessage app cards much easier to inspect and use in your app. ✨

Improvement

• The generated HTTP/OpenAPI types now include mini-app content and layout fields, so REST clients get the same structured data as the core SDK.
• API documentation was expanded with clearer service descriptions and mini-app field explanations.

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Version: 2.1.0

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🤖 This PR was auto-generated by Claude Code via the update-docs action in buildspace.

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