ui: improve qr code performance

[MarkNerdi996]

Summary

By using svelte-qrcode the qr code gets generated as a blog instead of rendered as dom elements.

Changelog

- use `svelte-qrcode` for qr code generation

Relevant Issues

Closes #4641

Testing

Platforms

Please select any platforms where your changes have been tested.

• Desktop
  • [ ] MacOS
  • [ ] Linux
  • [ ] Windows
• Mobile
  • [ ] iOS
  • [ ] Android

Instructions

Please describe the specific instructions, configurations, and/or test cases necessary to test and verify that your changes work as intended.

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Checklist

Please tick all of the following boxes that are relevant to your changes.

• [ ] I have followed the contribution guidelines for this project
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have added or modified tests that prove my changes work as intended
• [ ] I have verified that new and existing unit tests pass locally with my changes
• [ ] I have verified that my latest changes pass CI workflows for testing and linting
• [ ] I have made corresponding changes to the documentation