Feature: QR codes in certificates

[mphasize]

To enable verification of certificates, we will add QR codes pointing to the public webpages of certificates into the generated PDF files.

Placement (position and size) of QR codes should be customisable in the PDF template settings. Other QR code options might be exposed as needed (inverted color, error correction level, ...). QR Codes should be drawn as vectors, not pixelated images into the PDF.

Apart from the QR code, it should also be possible to add the certificate UUID to the PDF document.

• Add "certificate.id" ("Unique ID") as a text replacement variable in the template editor
• Add a feature to generate and draw QR codes vector graphics into the PDF
• Create a "QR Block" or setting in the template editor to configure the QR code (optional setting, on by default)
• Add a copy/paste feature for template layouts that includes the QR code settings
• Bonus: Add feature for right-aligned text boxes in the template editor
• Bonus: Improve optical alignment for punctuation marks in right-aligned text.
• Investigate/fix hydration bug regarding TextRow id`s --> the error comes up when parts of a template are saved without a block oder line id. Not sure how that happened in the first place, but it seems like currently ids will eventually get added when lines or blocks are edited. So the error is not dramatic and also self-fixing over time and nothing I want to fix right now. Eventually we need schema validation on the incoming layout JSON structure.