Force server exit at the end of main()

By default, the Java process exits when all non-daemon threads are
terminated.

The Android SDK might start some non-daemon threads internally,
preventing the scrcpy server to exit in some cases.

So force the process to exit explicitly.

PR #4213 <#4213>

server/src/main/java/com/genymobile/scrcpy/Server.java

@@ -170,7 +170,22 @@ private static Thread startInitThread(final Options options) {
         return thread;
     }
 
-    public static void main(String... args) throws Exception {
+    public static void main(String... args) {
+        int status = 0;
+        try {
+            internalMain(args);
+        } catch (Throwable t) {
+            t.printStackTrace();
+            status = 1;
+        } finally {
+            // By default, the Java process exits when all non-daemon threads are terminated.
+            // The Android SDK might start some non-daemon threads internally, preventing the scrcpy server to exit.
+            // So force the process to exit explicitly.
+            System.exit(status);
+        }
+    }
+
+    private static void internalMain(String... args) throws Exception {
         Thread.setDefaultUncaughtExceptionHandler((t, e) -> {
             Ln.e("Exception on thread " + t, e);
         });