fix(audio): use WebRTC VAD on iOS

crates/chanora_audio/Cargo.toml

@@ -17,7 +17,7 @@ sonora = "0.1"
 webrtc-vad = "0.4"
 
 # ndarray is required by ort's tensor construction API and by
-# Silero VAD ONNX inference across all platforms.
+# Silero VAD ONNX inference on non-iOS targets.
 ndarray = "0.17"
 
 # Opus encoder. tsclientlib already pulls this; we depend explicitly so
@@ -50,12 +50,6 @@ coreaudio-rs = "0.14"
 # on the main queue to avoid the VPIO RPC timeout on iOS simulator.
 dispatch2 = "0.3"
 
-[target.'cfg(target_os = "ios")'.dependencies]
-# ONNX Runtime Rust binding for Silero VAD v6 (P1 VAD_002). The official
-# iOS CocoaPod ships ONNX Runtime as a static framework, so iOS links it
-# into chanora_bridge at build time instead of loading a dylib at runtime.
-ort = { version = "2.0.0-rc.12", default-features = false, features = ["std", "ndarray"] }
-
 [target.'cfg(not(target_os = "ios"))'.dependencies]
 ort = { version = "2.0.0-rc.12", default-features = false, features = ["load-dynamic", "ndarray", "api-24"] }