feat: add Email Logs collection to store sent email metadata

[KoushalGH]

Description

Adds Email Logs collection to store metadata (to, subject, timestamp, status) for every sent email. Integrated logging into emailService.js.

Semver Changes

• Patch
• Minor
• Major

Issues

Closes #12

Checklist

• I have read the Contributing Guidelines

[KoushalGH]

@MD-IRFAN-RAJ done with this, please review it.

[KoushalGH]

@MD-IRFAN-RAJ please reply.

[MD-IRFAN-RAJ]

@KoushalGH Add images for easy reference in your description.

[MD-IRFAN-RAJ]

@all-contributors please add @KoushalGH for code
@all-contributors please add @indrasuthar07 for code
@all-contributors please add @Saitama9 for code

[allcontributors]

@MD-IRFAN-RAJ

I've put up a pull request to add @KoushalGH! 🎉

[MD-IRFAN-RAJ]

@all-contributors please add @indrasuthar07 for code

[allcontributors]

@MD-IRFAN-RAJ

I've put up a pull request to add @indrasuthar07! 🎉

[MD-IRFAN-RAJ]

@all-contributors please add @Saitama9 for code

[allcontributors]

@MD-IRFAN-RAJ

I've put up a pull request to add @Saitama9! 🎉