Scan: fix and clean up copy button ( proof )

[evilpeach]

Fixed: #2440

Implementation details

• Fix copy proof button styles
• Remove unused component and styles

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[render]

Your Render PR Server URL is https://d3n-scan-pr-2557.onrender.com.

Follow its progress at https://dashboard.render.com/static/srv-bt2b40oti7jetlceadj0.

[pzshine]

Please adjust this on smallMobile screen.