feat(core): ask for 20/33 words to unlock backup

[obrusvit]

Unlocking repeated backup is only possible with SLIP-39 extendable backup which contains shares of 20 or 33 words. It is UI bug to have the user choose from all options (12, 18, 20, 24, 33). This commit reduces the choices when unlocking repeated backup to (20, 33) for all models.

TODO:

• [x] click tests (9828605fee317ffc1bbcac605d2b3e8a654e45ca)
• [x] find a suitable home for RECOVERY_TYPE_<xyz> constants (684936f67bc663a5f72ca1d33011355969cbd5af)
• [x] is it possible to have reduced options also for regular backup check?
  • the answer is no
• [x] clippy doesn't like big size of enum variants of SelectWordCount
  • decided to silence this warning as I don't see a performance hit for the following reasons
    1. the larger variant predates the reduced option and it already worked with the larger one
    2. the enum is not instantiated frequently
    3. it makes the code simpler