feat: add physically explicit narrowband MUSIC

tests/unit/realtime-localizer.test.js

@@ -165,6 +165,98 @@ test("portable raw-map peak detection이 같은 band의 두 진원 후보를 강
   );
 });
 
+test("portable peak detection treats MUSIC noise projection as a minimum", () => {
+  const scan = {
+    z: 1,
+    xMin: 0,
+    xMax: 4,
+    yMin: 0,
+    yMax: 4,
+    columns: 5,
+    rows: 5,
+  };
+  const q = new Float64Array(25);
+  q.fill(1);
+  q[6] = 0.1;
+  q[18] = 0.2;
+  q[3] = 0.6;
+
+  const peaks = detectBandPeaks(q, scan, {
+    rawScale: "noise-projection",
+    objectiveDirection: "minimum",
+  });
+  assertEqual(peaks.length, 2, "two q minima exceed the merit threshold");
+  assertEqual(peaks[0].index, 6, "smallest q ranks first");
+  assert(
+    Math.abs(peaks[0].noiseProjection - 0.1) <= 1e-12,
+    "raw q is retained",
+  );
+  assertEqual(peaks[0].objectiveDirection, "minimum", "minimum objective is explicit");
+  assertEqual(
+    detectBandPeaks(
+      new Float64Array(25).fill(0.5),
+      scan,
+      {
+        rawScale: "noise-projection",
+        objectiveDirection: "minimum",
+      },
+    ).length,
+    0,
+    "flat q does not choose the first grid cell",
+  );
+});
+
+test("portable and streaming MUSIC consume unavailable auto-K windows without stalling", async () => {
+  const fixture = createFixture(256);
+  const musicConfig = {
+    ...fixture.config,
+    algorithm: "music",
+    normalization: "none",
+    stft: { fftSize: 64, hopSize: 64 },
+    musicSourceCountMethod: "mdl",
+    musicSourceCount: 1,
+  };
+  const plan = createLocalizationPlan(musicConfig);
+  const block = await localizeMultichannel({
+    plan,
+    channels: sliceChannels(fixture.channels, 0, 128),
+  });
+  assertEqual(block.status, "unavailable", "short auto-K block is typed unavailable");
+  assertEqual(
+    block.unavailable.reason,
+    "insufficient-snapshots-for-source-count-selection",
+    "unavailable reason is explicit",
+  );
+  assertEqual(block.frameCount, 2, "unavailable result preserves analyzed frame count");
+  assertEqual(block.bands.length, 0, "no arbitrary MUSIC map");
+  assertEqual(block.locations.length, 0, "no arbitrary location");
+
+  const stream = createStreamingLocalizer({
+    ...musicConfig,
+    analysisWindowSamples: 128,
+    analysisHopSamples: 128,
+    maximumBufferedSamples: 256,
+    maximumResultsPerCall: 2,
+  });
+  stream.append(fixture.channels);
+  const results = await stream.analyzeAvailable({
+    maximumResults: 2,
+  });
+  assertEqual(results.length, 2, "both unavailable windows are emitted");
+  assert(
+    results.every(
+      (result) =>
+        result.status === "unavailable" &&
+        result.locations.length === 0,
+    ),
+    "each window remains explicitly location-free",
+  );
+  const streamState = stream.getState();
+  assertEqual(streamState.completedAnalyses, 2, "unavailable windows commit");
+  assertEqual(streamState.failedAnalyses, 0, "unavailable is not a runtime failure");
+  assertEqual(streamState.bufferedSamples, 0, "stream advances past both windows");
+});
+
 test("CPU 분석 계획이 반복 geometry·steering 연산과 bin map 할당을 실제로 제거한다", async () => {
   const fixture = createFixture(128);
   const plan = createLocalizationPlan(fixture.config);