Allow user to stake entire balance

[kkosiorowska]

Currently, the user can select the entire balance in the form. However, if the user moves on to step two, signing the deposit transaction, receives the following error:

This happens because the fee is not taken from the selected amount, but from the user's balance, which is zero. In the task, it is necessary to explore the topic and find the best option to solve this problem.

[kkosiorowska]

Let's close this task because it is a duplicate. The problem should be solved in #537