Allow users to set a custom countdown timer (e.g., 15 minutes)

[imtahirabatool]

Description:

It would be great if users could set a countdown timer of their own choice instead of selecting from fixed options only. For example, being able to start a 15-minute timer or any custom duration would improve flexibility and user control.

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Suggested Improvement:

• Add an input field or dropdown to let users set a custom timer duration (e.g., 5, 15, 25, or any number of minutes).
• Ensure it integrates smoothly with the existing Pomodoro workflow and UI.

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Benefit:

This feature would make the app more user-friendly by supporting personal work styles and varying task durations.