Migrate date operations to Day.js for better parsing

[abhideepm]

[abhideepm]

Would like to take this up

[cal-overflow]

What is the benefit of Day.js over basic string parsing (current implementation)?

The current implementation parses the string and creates a JSON object that can be utilized by the frontend (public/app.js) which does not have direct access to node modules.

[abhideepm]

In my experience, date operations have too many edge cases to be handled (Like DST, Leap year, etc.) which I think are handled way better by libraries like Day.js as they are production ready. I think it'll be much more extensible if we need to add any other date related features in the future.