Remove obsolete INFORMATION_NEEDED.md and streamline README.md for clarity

- Deleted the INFORMATION_NEEDED.md file as it was no longer necessary for documentation.
- Revised README.md to enhance the overview of the home automation system, focusing on how services and CODESYS connectivity work.
- Updated project structure in README.md for better organization and clarity, including links to relevant documentation.

This update simplifies the documentation and improves the overall user experience for developers and users of the home automation system.

docs/README.md

@@ -1,30 +1,24 @@
-# Documentation Index
+# Documentation
 
-## Reference (Architecture & Setup)
-- [Architecture Overview](reference/architecture.md)
-- [Hardware Inventory](reference/hardware.md)
-- [Network Topology](reference/network.md)
-- [Setup Guide](reference/setup.md)
-- [Quick Reference](reference/quick-reference.md)
+Basics: **how home automation works**, **services**, and **CODESYS connectivity**.
+
+## Reference (architecture & setup)
+
+- [Architecture](reference/architecture.md) — Components and data flow
+- [Hardware](reference/hardware.md) — Raspberry Pi, EtherCAT, Zigbee
+- [Network](reference/network.md) — Topology
+- [Setup](reference/setup.md) — Installation order
+- [Quick reference](reference/quick-reference.md)
+
+## Services
+
+- [MQTT](integration/mqtt.md) — Broker (LXC)
+- [Node-RED](integration/nodered.md) — Automation and CODESYS bridge
+- [Home Assistant](integration/homeassistant.md) — Dashboard
+- [Zigbee2MQTT](integration/zigbee2mqtt.md) — Zigbee ↔ MQTT
 
 ## CODESYS
-- [CODESYS Configuration](codesys/codesys.md)
-- [CODESYS Export Guide](codesys/codesys-export-guide.md)
-- [CODESYS Project Analysis](codesys/codesys-analysis.md)
-- [CODESYS XML Analysis](codesys/codesys-xml-analysis.md)
 
-## Integration (Node-RED, MQTT, HA, Zigbee)
-- [Node-RED](integration/nodered.md)
-- [MQTT Broker](integration/mqtt.md)
-- [Home Assistant](integration/homeassistant.md)
-- [Zigbee2MQTT](integration/zigbee2mqtt.md)
-
-## Redesign (Structure & Implementation)
-- [Redesign Summary](redesign/redesign-summary.md) — **Start here for redesign**
-- [Light Naming Configuration](redesign/light-naming-configuration.md) — Configure lights per room
-- [Implementation Roadmap](redesign/redesign-implementation-roadmap.md)
-- [Structure Redesign Analysis](redesign/structure-redesign-analysis.md)
-- [Structure Comparison (Visual)](redesign/structure-comparison-visual.md)
-- [fb_switch Documentation](redesign/fb_switch-documentation.md)
-- [fb_switch Redesign Recommendation](redesign/fb_switch-redesign-recommendation.md)
-- [fb_switch Analysis Summary](redesign/fb_switch-analysis-summary.md)
+- [CODESYS configuration](codesys/codesys.md) — Runtime, EtherCAT, NVL
+- [PLC algorithm design](codesys/plc-algorithm-design.md) — Logic and I/O
+- **NVL (connectivity):** [codesys/src/NVL/README.md](../codesys/src/NVL/README.md) — UDP, NVL_In / NVL_Out, payload layout