added toast errors

[abhinav-m22]

• Closes #160

👨‍💻 Changes proposed:

Added toast error messages instead of simple JavaScript alerts to enhance the user experience. Proper coloring with styling and timeout animations have been considered

📝 Additional Notes

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✔️ Check List (Check all the applicable boxes)

• [x] My code follows the code style of this project.
• [x] The title of my pull request is a short description of the requested changes.
• [x] I am a participant of GSSOC23

[abhinav-m22]

@Fenrir-04 In the issue, level3 was mentioned... Please confirm