fix(regex): add missing 4th octet to Email address preset for IPv4 domains

[terminalchai]

Problem

The Email address preset regex in the Regular Expression operation was missing the 4th IPv4 octet in the bracketed address form (RFC 5321 address literals).

The IPv4 bracket group matched only three octets followed by a trailing dot:
\
\[(?:(?:(octet))\.){3}\]
\\

This means:

• ❌ \user@[1.2.3.4]\ — not matched (should be matched)
• ✅ \user@[1.2.3.]\ — false positive match (should not match)

Fix

Add the 4th octet group before the closing bracket, matching the correct regex already used in \ExtractEmailAddresses.mjs:
\
\[(?:(?:(octet))\.){3}(?:(octet))\]
\\

Now:

• ✅ \user@[1.2.3.4]\ — matches correctly
• ✅ \user@[192.168.0.1]\ — matches correctly
• ❌ \user@[1.2.3.]\ — correctly rejected

Changes

• \src/core/operations/RegularExpression.mjs\ — fixed the Email address preset regex
• \ ests/operations/tests/Regex.mjs\ — added regression test for IPv4-domain email addresses

Fixes #2150

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[C85297]

Hi @terminalchai , thank you for your pull request! I think we are already tracking this issue and have a fix ready here: #2167 . Could you check whether the changes in that pull request would satisfy your use case, or are there any other changes we need to make?

[terminalchai]

Thanks for pointing that out @C85297! Confirmed — PR #2167 was merged yesterday and fully covers the same fix (adds the 4th octet to the Email address preset regex and closes #2150). This PR is a duplicate and can be closed. Closing now.