Add feature: Add Timer CircularCountDownTimer

[cabdiris]

Description

Proposed Changes

i add CircularCountDownTimer and enable pausing and resuming:
Import circular_countdown_timer package:
Imported the circular_countdown_timer package to use the CircularCountDownTimer widget.

Introduced CountDownController into Timer controller:
Created a CountDownController named ccontroller to control the pause and resume functionalities of the CircularCountDownTimer

Updated FloatingActionButton onPressed Functions:
In the onPressed functions of the FloatingActionButton for stopping and pausing/resuming the timer and CircularCountDownTimer, I added if statements to calls to the _pauseTimer ,_resumeTimer,ccontroller.resume and ccontroller.pause.

Fixes #299

Replace #299 with the issue number which is fixed in this PR

Screenshots

Checklist

• Tests have been added or updated to cover the changes
• Documentation has been updated to reflect the changes
• Code follows the established coding style guidelines
• All tests are passing

[AdarshRawat1]

Fixes : #299

[MarkisDev]

Please add a preview (such as a screenshot or video) of the changes.