Inputted domain can be used directly in regex, causing an error

[m50d]

Current Behavior

https://github.com/ZooTools/email-spell-checker/blob/420dc73a72316848c2bd908c6fb95e4aa9aa0855/src/lib/suggest-email.ts#L90 constructs a regex by string manipulation, which causes an exception if we reach that line with a domain that contains invalid regex syntax.

Expected Behavior

Calling with any input should either suggest an email or fail cleanly (returning undefined), not throw an exception.

Steps to Reproduce the Problem

> const suggestedEmail4 = emailSpellChecker.run({
...   email: 'jorge@bigidaunashtnsuaeonsti.co)',
... })
Uncaught SyntaxError: Invalid regular expression: /co)$/: Unmatched ')'

Environment

• Version: 1.12.0
• Platform: Linux
• Node.js Version: v18.19.0