[Bug]: Calculate staked balance for required XOR amount

[ra9mls]

Preconditions

User has more than 100 euro in XOR staked balance

Steps to reproduce

1. Start registration flow
2. Register phone number
3. Approve email

Actual behavior

User sees not enough xor balance to start registration process

Expected behavior

User sees enough xor balance

Environment

{"label"=>"Production"}

OS version

No response

Additional context

No response

[2bogd]

doc needed, we have this balances, it is not clear what to use

[2bogd]

@bgodlin

[bgodlin]

@ra9mls could you offer additional context regarding the specific staking mechanism being used in the provided example?

[bgodlin]

Will be solved as part of https://github.com/sora-xor/sora-card-ios/issues/65

[bgodlin]

@ra9mls @2bogd please review https://github.com/sora-xor/sora-card/issues/60

[2bogd]

On test env: https://github.com/sora-xor/sora-card-ios/assets/99387689/ce247bc7-1f06-4c2c-b405-bf22cfb7ddfe