Add --audio-buffer

Expose an option to add a buffering delay (in milliseconds) before
playing audio.

This is similar to the options --display-buffer and --v4l2-buffer for
video frames.

PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>

app/src/cli.c

@@ -70,6 +70,7 @@ enum {
     OPT_LIST_ENCODERS,
     OPT_LIST_DISPLAYS,
     OPT_REQUIRE_AUDIO,
+    OPT_AUDIO_BUFFER,
 };
 
 struct sc_option {
@@ -119,6 +120,14 @@ static const struct sc_option options[] = {
                 "Unit suffixes are supported: 'K' (x1000) and 'M' (x1000000).\n"
                 "Default is 196K (196000).",
     },
+    {
+        .longopt_id = OPT_AUDIO_BUFFER,
+        .longopt = "audio-buffer",
+        .argdesc = "ms",
+        .text = "Add a buffering delay (in milliseconds) before playing audio. "
+                "This increases latency to compensate for jitter.\n"
+                "Default is 0 (no buffering).",
+    },
     {
         .longopt_id = OPT_AUDIO_CODEC,
         .longopt = "audio-codec",
@@ -1812,6 +1821,11 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case OPT_REQUIRE_AUDIO:
                 opts->require_audio = true;
                 break;
+            case OPT_AUDIO_BUFFER:
+                if (!parse_buffering_time(optarg, &opts->audio_buffer)) {
+                    return false;
+                }
+                break;
             default:
                 // getopt prints the error message on stderr
                 return false;