fix: Crash on invalid words

[tuliomir]

There were two events that triggered the validation of the words on the "Import Wallet" screen:

• Clicking the "Next" button at the bottom of the screen
• Clicking the native "Submit" button from the TextArea.

Each of these events had their own validation, which led to inconsistent app behavior and crashes when using the "Submit" button.

Acceptance Criteria

• In the "Import Wallet" screen, user must not receive an error by clicking "Submit" with an empty text
• Also must not receive an error with invalid words

Security Checklist

• Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. More dependencies increase the possibility of one of them being hijacked and affecting us.

Example interaction

output_480p.mp4