Audio: WAV + tinyaudio, Ambient-Emitter mit Distance ramps; artist.md

engine/wav.rs (Decoder) und render/audio.rs (Mixer, 8 SFX-Voices +
Loop-Voice je Emitter) aus irl3d eingebettet; Emitter-Logik headless in
engine/audio.rs. Empties mit sound/radius-Property senden positional,
play_sound-Signale laufen als SFX über Session::take_sounds.
Platzhalter-Sounds + Emitter in der Testszene; artist.md fasst die
Content-Regeln für die Autorin zusammen.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Cargo.toml

@@ -8,5 +8,6 @@ bladeink = "1.2.5"
 bytemuck = { version = "1.25.0", features = ["derive"] }
 pollster = "0.4.0"
 serde_json = "1"
+tinyaudio = { version = "2", default-features = false, features = ["pulse"] }
 wgpu = "29.0.3"
 winit = "0.30.13"