Feature: Option to choose sounds during meditation

[vayulab]

Problem

Currently, users can only select gongs at intervals. There's no option to play ambient sounds (rain, ocean, white noise, etc.) during the meditation session.

Proposed solution\nAdd a sound selection feature that allows users to:

• Choose from a library of ambient sounds (nature sounds, white noise, binaural beats, etc.)
• Optionally combine ambient sounds with gongs
• Adjust volume for each sound layer

Acceptance criteria

• Sound library with at least 3-5 ambient options
• UI to select and preview sounds before meditation
• Sounds play continuously during meditation session
• Option to disable sounds (current behavior)
• Volume controls for each sound type

Notes

Consider audio licensing and app size impact.