Fix(iban): return error instead of throwing on non-alphanumeric characters

[eugeniobaglieri]

Connection with issue(s)

Close #168

Solution description

• isIBAN now checks regex.hasMatch(iban) before computing the checksum, so the documented regex is applied. The default regex is unchanged.
• The checksum computation is wrapped in try/catch returning false. This covers the case the default regex lets through (\w matches _) and any custom, more permissive regex.
• Guard clauses are split into one condition per line.

To Do

• [ x] Read contributing guide
• [ x] Check the original issue to confirm it is fully satisfied
• [ x] Add solution description to help guide reviewers
• [ x] Add unit test to verify new or fixed behaviour
• [ x] If apply, add documentation to code properties and package readme

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.21%. Comparing base (2e108a1) to head (e9f11be).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #169   +/-   ##
=======================================
  Coverage   99.20%   99.21%           
=======================================
  Files          95       95           
  Lines        1012     1013    +1     
=======================================
+ Hits         1004     1005    +1     
  Misses          8        8           

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