[FEAT]: added 'add topic' page for student

[trinetra110]

📋 Description

Added a "add topic" page for student (frontend only) and added the link in the student's main page, keeping in mind the responsiveness across all devices.

🔨 Changes Made

• Created new files "add_topic.html", "add_topic.css" and "add_topic.js"
• Added the link to "add_topic.html" in "main_page.html"

✅ Checklist

Before submitting the PR, please make sure you have completed the following:

• I have followed all the guidelines mentioned in CONTRIBUTING.md.
• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation (if applicable).
• I have tested it locally and it works fine.
• Any dependent changes have been merged and published in downstream modules.

🏷️ Types of Changes

What type of changes does your code introduce? (Check all that apply)

• Bug fix (non-breaking change which fixes an issue) 🐛

• New feature (non-breaking change which adds functionality) ✨

• UI enhancement (non-breaking change which enhances UI) 🎨

• Documentation update 📚

• Fixes Add a "Add topic" page for Student #334

📸 Screenshots (if applicable)

• Desktop/laptop

• Phone

• Tab

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Thank you for contributing to Research Nexus! We look forward to reviewing your PR and getting it merged!

[trinetra110]

@Harshdev098 I have made the required changes. Please review it and add the 'hacktoberfest', 'hacktoberfest-accepted', 'gssoc-ext' and a 'level' tag.

[Harshdev098]

@trinetra110 Instead of students name you can make it Departments field if you can make it as option type fields it will be good like there in form-filling.html

[trinetra110]

@trinetra110 Instead of students name you can make it Departments field if you can make it as option type fields it will be good like there in form-filling.html

@Harshdev098 I have made the changes. Please review and add the labels.

[github-actions]

🎉🎉 Thank you for your contribution! Your PR #342 has been merged! 🎉🎉