test: add log file checking to debug audio routing test failures

Co-authored-by: aider (deepseek/deepseek-coder) <aider@aider.chat>

test_audio_routing.c

@@ -188,6 +188,25 @@ static int start_looper(const char *client_name) {
         return -1;
     }
     
+    // Check log file for debug messages
+    FILE *log = fopen("jack-looper.log", "r");
+    if (log) {
+        char line[256];
+        int has_debug = 0;
+        while (fgets(line, sizeof(line), log)) {
+            if (strstr(line, "Channel") && strstr(line, "nframes")) {
+                has_debug = 1;
+                printf("    [LOG] %s", line);
+            }
+        }
+        fclose(log);
+        if (!has_debug) {
+            printf("    [LOG] No process callback debug messages found\n");
+        }
+    } else {
+        printf("    [LOG] Could not open jack-looper.log\n");
+    }
+    
     return 0;
 }