Add mechanical keyboard sound effects

[niklasmarderx]

What

Add optional typing sound effects that play on each keystroke, simulating different mechanical keyboard switches.

Why

Sound feedback makes typing more satisfying and can help with rhythm. Many typing trainers (monkeytype, keybr) offer this feature.

How

1. src/services/SoundService.ts already exists as a foundation
2. Add 3-4 sound profiles: Cherry MX Blue (clicky), Cherry MX Brown (tactile), Cherry MX Red (linear), Typewriter
3. Use short audio samples (public domain / CC0) or generate them with the Web Audio API
4. Play on keydown events in the typing area
5. Add volume control and sound profile selection in settings
6. Respect the user's preference (off by default)

Resources

• Web Audio API
• Free keyboard sounds: freesound.org