added a dark mode icon ata login page which toggeles and applies dark mode

[singhshikha01]

added a dark mode icon at login page which toggeles and applies dark mode

Related Issue

[ISSUE NO : #716 ]

Description

[added a dark mode icon at login page which toggeles and applies dark mode]

Type of PR

• [X] Bug fix
• [X] Feature enhancement
• [ ] Documentation update
• [ ] Other (specify): ___

Screenshots / Videos (if applicable)

Checklist:

• [X] I have performed a self-review of my code.
• [X] I have read and followed the Contribution Guidelines outlined in the project's documentation.
• [X] I have thoroughly tested the changes before submitting this pull request.
• [X] I have provided relevant issue numbers, screenshots, and videos after making the changes.
• [X] I have commented my code, particularly in hard-to-understand areas.

Additional Context:

[Include any additional information or context that might be helpful for reviewers. This could include details about any design decisions, potential impacts, or alternative approaches considered.]

[github-actions[bot]]

Excellent work🚀🚀, @singhshikha01! Thank you for submitting your pull request. Your contribution is valuable, and we appreciate your efforts to improve our project. We will review your changes promptly and provide feedback. Keep up the excellent work! Please remember to check our documentation and guidelines.

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