fix : added text badges to streak milestone notification emails

[tmdeveloper007]

What does this PR do?

Removes emoji HTML entities from streak milestone notification emails and replaces them with styled text badges.

Summary of What Has Been Done

Replaced emoji HTML entities in src/lib/notification-senders/streak.ts with styled text badges. The MILESTONE_MESSAGES constant now uses a badge field (e.g. "7 DAYS", "30 DAYS") instead of emoji HTML entities. The HTML email template renders the badge as a styled monospace text element.

Changes Made

• src/lib/notification-senders/streak.ts:
  • Renamed emoji field to badge in MILESTONE_MESSAGES
  • Replaced 🔥 (fire) with "7 DAYS"
  • Replaced 🏆 (trophy) with "30 DAYS"
  • Replaced 💎 (gem) with "100 DAYS"
  • Replaced 👑 (crown) with "1 YEAR"
  • Updated HTML template to render badge as styled monospace text instead of emoji character

Impact it Made

• Streak milestone emails no longer contain emoji characters
• Notifications remain visually distinct through styled text badges
• All notification code now complies with the project-wide no-emoji policy

Closes 1381

Note: Please assign this PR to the tmdeveloper007 account.

[github-actions]

✅ Security Scan: Clean

No suspicious patterns detected. The official Copilot bot will provide detailed AI feedback shortly.

⭐ If you enjoyed contributing, please consider starring the repository!

[github-actions]

👋 Hey @tmdeveloper007, it looks like you didn't use our PR template!

The section ## Related issue is missing from your PR description.

Please update your PR description to include all required sections so we can review this properly:

• ## What does this PR do? — What does this PR do? Which issue does it fix?
• ## Related issue — Link the issue with Fixes #N
• ## Checklist — Have you ticked off the quality checklist?

You can find the full template in CONTRIBUTING.md. Just edit your PR description and the needs-details label will be removed automatically. 🙌

[github-actions]

👋 Hey @tmdeveloper007! Thanks for your contribution! 🎉

It looks like this PR isn't linked to any issue yet.

Please edit your PR description and add a closing keyword so we can track this properly, for example:

Fixes #<issue-number>

💡 You can link multiple issues if needed (e.g. Fixes #12, Closes #34).
If you're working on something that doesn't have an issue yet, please open one first and then link it here.

Once you've updated the PR description the check will re-run automatically. 🙌

[github-actions]

📋 GSSoC Label Validation Report

✅ All label requirements met. This PR passes the pre-merge label check.

---

📖 Label Reference

Category	Valid Labels	Rules
Approval	gssoc:approved	Required to score and merge
Difficulty	level:beginner / intermediate / advanced / critical	Exactly one is required
Quality	quality:clean / quality:exceptional	Optional (max one); exceptional requires reviewer comment
Type	type:bug, type:feature, type:docs, type:testing, type:refactor, type:design, type:accessibility, type:performance, type:devops, type:security	At least one is required
Blocking	gssoc:invalid, gssoc:spam, gssoc:ai-slop	Excludes PR from scoring and blocks merge

[vercel]

@Ixotic27 is attempting to deploy a commit to the ixotic27-8245's projects Team on Vercel.

A member of the Team first needs to authorize it.

[Ixotic27]

LGTM! Verified and approved. Great contribution!

[github-actions]

🎉 Congratulations @tmdeveloper007! Your PR has been successfully merged. 🚀

Thank you for contributing to The Leetcode City. Your work helps us build a better platform for the community.

⚠️ Important for GSSoC Contributors:
Please make sure you are following all contribution guidelines. All important announcements and point claims happen through the official GSSoC channels.

Keep building! 💻✨

[Ixotic27]

LGTM! Approved and verified. Great contribution!