Update the keychain's service creation step in the global process

### Is your feature request related to a problem?

Currently, the service is created at the beginning of the process when a new website is created.
If the user decides not to pay the fee (or cannot), the site is not deployed but the service still exists

### Describe the solution you'd like

2 possibilities
- Make a rollback by updating the keychain without the service (which requires a new validation on the wallet side)
- Create the service after the validation of global fees by the user.

### Additional context

The second solution is blocked by a check on the address derivation and keypair methods which verify that the service exists in the keychain. It is therefore necessary either to put a parameter to exclude this control in certain cases (this also requires to provide the derivation path instead of the service name) or to manage the new keychain service on the wallet side in memory in a session.

Start by tracing the global process where the keychain service is created and the address derivation and keypair checks that require the service. Compare the rollback and delayed-creation options described in the issue, including their wallet-side implications. Done means an unpaid deployment does not leave an unintended keychain service, with the chosen validation behavior agreed and verified.

Written by the indexing model from the issue text.