chore: graphic adjustments in contact details

[madbob]

Here some random adjustment for ContactDetails, including:

• a proper frame for the QR modal. The closing button was almost invisible...
• a review of the "clone contact" modal, unintentionally broken by global CSS rules
• some cleanup of the embedded CSS (given that ContactDetails stays quite messy...)

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[hamza221]

/backport to stable8.8

[hamza221]

/backport to stable8.7

[codecov]

Codecov Report

❌ Patch coverage is 0% with 8 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/components/ContactDetails.vue	0.00%	8 Missing ⚠️

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