Update documentation for Home Assistant light management and room configuration

- Added a new section in README.md for creating and managing lights by room in Home Assistant, linking to a focused guide.
- Enhanced the all-lights-and-rooms.md documentation with a reference to the new guide for clarity on entity creation and room assignment.
- Made minor adjustments to the room-config.js file, commenting out outdated device-to-room mappings to improve code clarity.

This update improves the documentation and usability for users managing lights and rooms in Home Assistant.

docs/README.md

@@ -21,6 +21,7 @@ Basics: **how home automation works**, **services**, and **CODESYS connectivity*
 
 - [Living Room flow](integration/nodered-livingroom-flow.md) — Test flow, NVL send, Action node, sync
 - [All lights and rooms](integration/all-lights-and-rooms.md) — Scale to all lights: config, HA entities (YAML bulk), checklist
+- [HA: create and manage lights by room](integration/ha-lights-and-rooms.md) — Create entities, assign to rooms (Areas), sync with room-config.js
 - [Living Room analysis](integration/nodered-livingroom-analysis.md) — Current nodes and wiring (from live Node-RED)
 
 ## CODESYS