Capture application screenshot when copying Unity console context

[dudetru25]

Summary

• capture the current Camera.main application view when the Unity toolbar copy button is clicked
• write the PNG to the stable Unity temp path unity-cursor-toolkit-application.png, replacing the prior image on every successful click
• append the absolute screenshot path to the copied profiler and console context
• preserve the existing clipboard output when no main camera exists or capture fails
• restore camera/render state and release temporary textures in all cases

User impact

The copied diagnostics now tell an agent where to load the screenshot that matches the current Unity application state. Repeated clicks reuse one temp path, so stale captures do not accumulate.

Validation

• npm run validate
• 206 tests passed across runtime, simplified-context, and remote-shell suites
• vendor integrity passed
• npm audit reported 0 vulnerabilities
• independent read-only review found no functional issues

Limits

The screenshot is the application/game camera view from Camera.main. It does not capture the full desktop or Unity Editor chrome.

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