Introduce Dynamic constants, Theming option

[ajaman190]

Introduce dynamic constants, theming option #172

Summary:
This pull request introduces a new feature of theming and making the app more dynamic to different screens.

Issues:

1. Screens and components of the app are not dynamic, i.e., they are not changeable with the change in screen size, and all their values are hard-coded.
2. The app does not have a feature of theming.

Issue resolved Checklists:

• Introducing new dynamic constants that dynamically resize the components, fonts, and other elements on the screen.
• Adding a theming option to the app, allowing users to change the look and feel of the app quickly and efficiently.
• Revamping the login and signup pages to make them dynamic and customizable.

Recording:
I have tested these changes thoroughly to ensure that they work as expected.

Project.1.mp4

Ignore the first three commit they belong to the last pr # 176 (login and signup).

@shehand Please let me know if there are any issues or concerns with this pull request. I am happy to address any feedback or suggestions that you may have.

[ajaman190]

@shehand kindly review this pull request. I am looking forward for feedback.