[Feature/Improvement] Improve Audio Files

**Purpose:** As a user, I want sound effects to be smooth and consistent so that audio cues are clear and never skipped.

**More details:** Currently, sound effect files vary in length and some start or end abruptly, creating harsh or jarring audio experiences. All sound effect files should be trimmed to a consistent, short duration and processed with fade in/fade out envelopes to ensure clean playback.

**Acceptance Criteria:**
- All sound effect files are under 500ms (0.5 seconds) in duration
- All sound effect files have a fade in applied at the start to prevent clicking or abrupt onset
- All sound effect files have a fade out applied at the end to prevent clipping or abrupt cutoff
- Fade durations are consistent across all files (e.g. 10–20ms fade in, 20–30ms fade out)
- All updated files are verified to play without audible pops, clicks, or harsh transitions on both iOS and Android

Find the sound effect files in the project's assets directory. Use an audio editor like Audacity to trim each file to under 500ms and apply consistent fade-in (10-20ms) and fade-out (20-30ms). Test playback on both iOS and Android simulators or devices to ensure no audible pops or clicks.

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