feat: add independent full-band activity workflow

tests/unit/spectral-flux.test.js

@@ -1,5 +1,6 @@
 import {
   computeDixonSpectralFlux,
+  estimateDixonSpectralFluxWorkload,
   pickCausalSpectralFluxPeaks,
 } from "/packages/acoustics-core/spectral-flux.js";
 
@@ -90,6 +91,19 @@ test("Dixon flux는 Hamming linear magnitude의 양의 차이를 full DFT에서
   assertEqual(result.workload.positiveDifferenceBytes, 64, "raw bin bytes");
   assertEqual(result.workload.outputBytes, 128, "total returned typed-array bytes");
   assertEqual(result.workload.maximumOutputBytes, 128, "caller output limit");
+  const preflight = estimateDixonSpectralFluxWorkload({
+    sampleCount: 8,
+    fftSize: 4,
+    hopSize: 4,
+    maximumOutputBytes: 128,
+  });
+  assertEqual(preflight.frameCount, result.frameCount, "preflight frame count");
+  assertEqual(preflight.outputBytes, result.workload.outputBytes, "preflight output bytes");
+  assertEqual(
+    preflight.estimatedPeakTypedArrayBytes,
+    result.workload.estimatedPeakTypedArrayBytes,
+    "preflight peak typed-array bytes",
+  );
 });
 
 test("Dixon flux는 silence와 incomplete tail을 패딩 없이 처리한다", () => {