Make a slider for selecting different brush size.

[rishidyno]

Currently, we only have 3 brush size options. A slider will be a better option and UI improvement.

[Smarshal21]

@yash10019coder @rishidyno sir could you please assign this issue to me

[rishidyno]

@Smarshal21 I have assigned this issue to you, feel free to ask if you have any doubts.

[rishidyno]

@Smarshal21 are you working on this issue?

[Smarshal21]

Yes sir . ill just make a commit in 30 mins