deps(transcription): drop whisper-cpp features from transcribe-rs — whisper-rs is sole Whisper backend

crates/transcription/Cargo.toml

@@ -7,8 +7,8 @@ description = "Speech-to-text engine wrappers, model management, and inference c
 [dependencies]
 kon-core = { path = "../core" }
 
-# Unified STT engine (Parakeet via ONNX, Whisper via whisper.cpp)
-transcribe-rs = { version = "0.3", features = ["onnx", "whisper-cpp", "whisper-vulkan"] }
+# Parakeet via ONNX. Whisper is handled directly via whisper-rs below.
+transcribe-rs = { version = "0.3", default-features = false, features = ["onnx"] }
 
 # Async runtime for spawn_blocking
 tokio = { version = "1", features = ["rt", "sync"] }