feat: Refactor & Add Edit Subject Functionality

[criticic]

Description

Sorry for the delay though. Refactored the code to move the edit/create subject dialogue to another file, and implemented the edit subject feature

Related Issue

Fixes #2

Type of Change

• [ ] Bug fix
• [x] New feature
• [ ] Documentation update

Screenshots (if any):

Please add screenshots to be easily reviewable

Checklist

• [ ] My code follows the style guidelines of this project
• [x] 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
• [x] My changes generate no new warnings

[criticic]

not sure why the two tests are failing

[Varun-Kolanu]

not sure why the two tests are failing

Yeah that's okay label-pr and android-build kisika nhi ho rha tha Abhi mann bhi nhi hai unko change karne ka

I too am not sure why commut-style is failing

[Varun-Kolanu]

@criticic Nice one. But not sure why the Grade and Marks are not being rendered. Can you look into that?

[criticic]

fixed it!

[Varun-Kolanu]

Cool

Thanks for the PR!