Missing identity validation when looking for trader information

[sallymoc]

When entering data in the public id field in the Home screen and tapping "Lookup Trader" the app is not validating the identity entered is correct

this gives the following result

Whether the user does the search or modifies the URL manually (https://qx.qubic.org/entities/), the app should validate the entity is valid (length 60 and the checksum of the last 4 characters) before to call any service in the backend

[qubicmio]

The backend returns a HTTP 400 error (Bad request) in this case. Maybe it is enough to use the status code for identifying invalid IDs.