Seat QR codes

Each QR code has a numerical representation as well. The number is generated with the Seat and it never changes.

Ideally, only the last 4 digits must be entered (marked with blue in this docs, in the frontend, and in the image we send to the Seats via email).

The numbers marked with red are "dangerous" ones, that are most likely to differ if the Seat comes to the wrong location or at the wrong date. It is marked with red to make it easier for the Access Control man to spot the difference.

This allows a unique code for each seat and makes it very easy to type the code in as only the last 4 digits change. This means in the frontend everything before the last 4 digits can be prefilled.
We calculate the last 4 digit with: QRCode.id % 10000.
We could have the same code, but in case it wouldn't be enough, we can increase the modulus.