Enhancement: Adding dismiss notification for Timers

[kushchoudhary98]

Description

This PR adds the support for showing the dismiss notification when the timer is up & being able to dismiss the timer from notification itself.

Proposed Changes

• Added new methodChannel dismissTimer.
• Added logic for sending message to native side for showing notification & receiving the dismiss action message.
• Added CREATE TABLE to onCreate function in TimerDatabaseHelper.kt to resolve timers table related issues.

Screenshots

WhatsApp.Video.2025-04-15.at.01.01.13.mp4

Fixes #820

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