Better tests and more user feedback while doing transcription; WIP.

src/lib/models.ts

@@ -256,7 +256,7 @@ export function estimateDefaultDownloadBytes(
 
 export const DEFAULT_MODEL_ID = "onnx-community/whisper-tiny.en";
 
-/** UI default: let the worker probe WebGPU and fall back to WASM (D-004). */
+/** UI default: worker probes WebNN → WebGPU → WASM in order (D-004, D-017). */
 export const DEFAULT_DEVICE_PREFERENCE: DevicePreference = "auto";
 
 export const DEFAULT_TASK: WhisperTask = "transcribe";