Trace member file requests in debug category

src/member_files/protocol.c

@@ -107,3 +107,9 @@ const char* mf_status_text(int status) {
         "Busy", "File changed", "Storage full", "I/O error", "Invalid packet", "Hash mismatch", "Cancelled", "Timeout" };
     return status >= 0 && status <= MF_TIMEOUT ? texts[status] : "Unknown error";
 }
+
+const char* mf_command_text(int command) {
+    static const char* commands[] = { "SWEEP", "LIST", "STAT", "READ", "BEGIN_WRITE", "WRITE", "COMMIT", "ABORT",
+                                      "MKDIR", "RENAME", "REMOVE" };
+    return command >= 0 && command <= MF_REMOVE ? commands[command] : "UNKNOWN";
+}