feat: add neoregex package

[officialasishkumar]

Summary

• Add a neoregex package definition using upstream GitHub Releases.
• Select the amd64 .deb asset published by NeoRegex.
• Add neoregex to the main manifest.

Validation

• Ran bash -n 01-main/packages/neoregex.
• Confirmed the definition resolves the latest amd64 .deb URL and published version from GitHub release JSON.
• Downloaded the current amd64 .deb and confirmed Package: neoregex with dpkg-deb -f.

Closes #1629

[cubic-dev-ai]

No issues found across 2 files

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

_{Auto-approved: This is a standard addition of a new package definition. The changes are isolated to the new package and its entry in the manifest, with no risk to core system logic.}