ensure user isn't removing invalid path

examples/companion_radio/MyMesh.cpp

@@ -1358,6 +1358,11 @@ void MyMesh::checkCLIRescueCmd() {
       // get path from command e.g: "rm /adv_blobs"
       const char *path = &cli_command[4];
 
+      // ensure path is not empty, or root dir
+      if(!path || strlen(path) == 0 || strcmp(path, "/") == 0){
+        Serial.println("Invalid path provided");
+      } else {
+
         // remove file
         bool removed = _store->removeFile(path);
         if(removed){
@@ -1366,6 +1371,8 @@ void MyMesh::checkCLIRescueCmd() {
           Serial.println("Failed to remove file");
         }
 
+      }
+
     } else if (strcmp(cli_command, "reboot") == 0) {
       board.reboot();  // doesn't return
     } else {