voice: replace Whisper with sherpa-onnx, live words from Kroko and the final words from Parakeet

Models download in Settings instead of shipping in the APK. Credits for the engine and models are in About.

gearslip/src/main/java/com/k2fsa/sherpa/onnx/OfflineStream.kt

@@ -0,0 +1,43 @@
+// From sherpa-onnx v1.13.8 (Apache-2.0, https://github.com/k2-fsa/sherpa-onnx), kotlin-api.
+package com.k2fsa.sherpa.onnx
+
+class OfflineStream(var ptr: Long) {
+    init {
+        require(ptr != 0L) { "Failed to create native OfflineStream" }
+    }
+
+    fun acceptWaveform(samples: FloatArray, sampleRate: Int) =
+        acceptWaveform(ptr, samples, sampleRate)
+
+    fun setOption(key: String, value: String) = setOption(ptr, key, value)
+
+    fun getOption(key: String): String = getOption(ptr, key)
+
+    protected fun finalize() {
+        if (ptr != 0L) {
+            delete(ptr)
+            ptr = 0
+        }
+    }
+
+    fun release() = finalize()
+
+    fun use(block: (OfflineStream) -> Unit) {
+        try {
+            block(this)
+        } finally {
+            release()
+        }
+    }
+
+    private external fun acceptWaveform(ptr: Long, samples: FloatArray, sampleRate: Int)
+    private external fun setOption(ptr: Long, key: String, value: String)
+    private external fun getOption(ptr: Long, key: String): String
+    private external fun delete(ptr: Long)
+
+    companion object {
+        init {
+            System.loadLibrary("sherpa-onnx-jni")
+        }
+    }
+}