feat: add emulate_device_profile tool

[hiowenluke]

• add predefined mobile device profiles and CDP emulation logic
• register emulate_device_profile tool, document usage and Copilot prompt example
• cover the new tool with automation tests and update the tool listing

[google-cla]

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[albertehc]

Any updates on this feature?
It would be interesting to be able to emulate a mobile device from the MCP