docs: add silk codec docs

docs/README.md

@@ -17,4 +17,8 @@
 
 # QQBot
 
-[QQBot](qqbot.md)
+[QQBot](qqbot.md)
+
+# Silk-Codec
+
+[Silk-Codec](silk.md)

docs/silk.md

@@ -0,0 +1,28 @@
+# Silk Codec
+
+> 简单封装了Silk codec
+
+## 解码
+
+```kotlin
+fun main() {
+    val inputStream: InputStream = ...
+    val inputStreamSilkBytes: ByteArray = inputStream.decodeToSilk()
+
+    val file: File = File("path/to/silk")
+    val fileSilkBytes: ByteArray = file.decodeToSilk()
+}
+```
+
+## 编码
+
+```kotlin
+fun main() {
+    val sampleRate = 8000  // 采样率
+    val inputStream: InputStream = ...
+    val inputStreamSilkBytes: ByteArray = inputStream.encodeToSilk(sampleRate)
+
+    val file: File = File("path/to/silk")
+    val fileSilkBytes: ByteArray = file.encodeToSilk(sampleRate)
+}
+```