Make a 32-byte dbEncryptionKey required

[bwcDvorak]

Is your feature request related to a problem?

dbEncryptionKey is technically optional in the rust backend. However, there isn't really any scenario other than maybe testing where you would want the data to be unencrypted. iOS hard fails if you don't pass one in; React Native should do the same.

Describe the solution to the problem

make react native require a dbEncryptionKey and make it more explicit that it needs to be 32 bytes

Describe the uses cases for the feature

No response

Additional details

No response