Main-screen recordings list, player actions, background recording, exports (1.4.0-alpha)

- Main screen: recordings list at the bottom (newest first); removed the separate
  library screen and the top-right link
- Player: delete/rename/share/export, no autoplay, embedded-marker fallback
- Word-level tap-to-seek from Whisper token timestamps (length fallback)
- Export transcripts as .txt + .srt to Downloads
- RecordingService: microphone foreground service for background recording
- FileProvider for sharing on Android 9 and older
- StreamingResampler extracted to its own class + JUnit regression tests
- Bump to 1.4.0-alpha (versionCode 6)

1 files changed, 41 insertions, 0 deletions

diff --git a/app/src/test/java/com/wuhei/reccoon/StreamingResamplerTest.java b/app/src/test/java/com/wuhei/reccoon/StreamingResamplerTest.java
new file mode 100644
index 0000000..6e4cdcd
--- /dev/null
+++ b/app/src/test/java/com/wuhei/reccoon/StreamingResamplerTest.java
@@ -0,0 +1,41 @@
+package com.wuhei.reccoon;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import java.util.Random;
+
+/** Regression tests for the streaming resampler. */
+public class StreamingResamplerTest {
+
+    @Test
+    public void longStreamOfFullChunksDoesNotThrow() {
+        StreamingResampler resampler = new StreamingResampler(44100, 16000);
+        float[] chunk = new float[8192];
+        long total = 0;
+        for (int i = 0; i < 400; i++) {
+            for (int j = 0; j < chunk.length; j++) {
+                chunk[j] = (float) Math.sin((i * 8192 + j) * 0.01);
+            }
+            total += resampler.process(chunk).length;
+        }
+        assertTrue(total > 1_000_000);
+    }
+
+    @Test
+    public void oddChunkSizesDoNotThrow() {
+        StreamingResampler resampler = new StreamingResampler(44100, 16000);
+        Random random = new Random(1);
+        long total = 0;
+        for (int i = 0; i < 3000; i++) {
+            int n = 1 + random.nextInt(3000);
+            float[] chunk = new float[n];
+            for (int j = 0; j < n; j++) {
+                chunk[j] = random.nextFloat() * 2f - 1f;
+            }
+            total += resampler.process(chunk).length;
+        }
+        assertTrue(total > 0);
+    }
+}