Bugfix added comprehensive email regex pattern

[SumithThota]

PR Description:

Fixes Issue : #1997

Enhanced Email Validation Regex in Client Script.
The existing email regex pattern: ^[^\s@]+@[^\s@]+\.[^\s@]+$ used in the source fails to handle several edge cases and may incorrectly validate or reject certain legitimate email formats, such as:

1. Emails with quoted local parts ("john.doe"@example.com)
2. Emails with dots within the local segment (user.name@example.com)
3. Emails using IP addresses as domains (user@[192.168.0.1])

Proposal

Update the email regex pattern to: ^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$

This pattern handles:

• Quoted local parts
• Dots within the local segment
• IP-based domains
• Complex but valid email formats

Pull Request Checklist

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[SapphicFire]

Looks good to me, thank you