Update Node-RED configuration and documentation for room management

- Added node-red/config_files/flows_cred.json to .gitignore to prevent committing sensitive credentials.
- Updated documentation references to the new location of room-config.js in node-red/config_files/ for clarity.
- Removed the obsolete room-config.js file, centralizing configuration management.

This update enhances security and improves the organization of Node-RED configuration files, ensuring better management of room settings.

node-red/config_files/node-red-contrib-home-assistant-websocket.json

@@ -0,0 +1,12 @@
+{
+  "nodes": {
+    "6d1793815598b149": {
+      "isEnabled": true
+    }
+  },
+  "issues": {
+    "hidden": [
+      "fe5612a41399f1f5"
+    ]
+  }
+}