Use data_description in config_flow for WLED

homeassistant/components/wled/strings.json

@@ -129,6 +129,9 @@
       "init": {
         "data": {
           "keep_master_light": "Add 'Main' control even with single LED segment"
+        },
+        "data_description": {
+          "keep_master_light": "This ensures the master light is always there, in case you are automating segments to appear and remove dynamically."
         }
       }
     }