feat: add address validation and formatting in address book command

[aapsi]

Summary

• Main Change:
  Added address validation and formatting to the address book command.

Explanation of Changes:

• Imported a new helper function, validateAndFormatAddress, from ../utils/index.js.
• When adding or updating an address in the address book, the code now:
  • Calls validateAndFormatAddress on the input address.
  • If the address is invalid (the function returns a falsy value), the command exits early without saving the address.
  • Only a valid, formatted address is saved to the address book under the given label.
• This validation logic was added both when adding a new address and updating an existing one.

Impact:
This change improves the reliability of the address book by ensuring that only properly validated and formatted addresses are stored, reducing potential errors from invalid addresses.

Changes: