Is your feature request related to a problem? Please describe.

After #3346 it might a good idea to check if any information in appdata.xml could be update.

Describe the solution you'd like

The main candidate is various urls:

• switching main homepage URL to cutter.re from docs
• use appropriate tag for link to help/docs
• github issue tracker link
• translation contribution link (either the page in docs or link to crowdin)

Describe alternatives you've considered

Additional context