feat: Add Pomodoro Presets (Focus, Short Break, Long Break) to Focus Mode

[sahare-mayur-0071]

Problem

Currently, the Focus Mode in the application only allows users to set a custom timer duration manually. Users have to type in standard Pomodoro intervals (like 25, 5, or 15 minutes) every single time they want to start a study session or take a break.

Proposed Improvement

Add quick-select preset buttons in the Focus Mode UI for standard Pomodoro intervals:

• Focus (25 minutes)
• Short Break (5 minutes)
• Long Break (15 minutes)
  I will update index.html to include the buttons and js/app.js to handle updating the timer when clicked.

Why improvement is needed

This improves the user experience by making it much faster and more frictionless for students to use standard study intervals, saving them from manual typing.

Expected Result

When a user clicks on one of the preset buttons, the timer duration will automatically update to the corresponding preset time without requiring any keyboard input.

Alternatives Considered

We could use a dropdown menu for presets, but dedicated buttons are faster and require fewer clicks.

Additional Context

I am participating in GSSoC 2026 and would love to work on this! Could you please assign this issue to me so I can implement it and submit a Pull Request?

[sahare-mayur-0071]

.assign