KC868-A16v3 ESPHome yaml for home assistant

[hans-martijn]

If you updated to the latest esphome, you have to alter the yaml for over the air updates:

# Before (implicit OTA in web server)
web_server:
port: 80

# After (explicit OTA platform required)
web_server:
port: 80

ota:
- platform: esphome # Your existing OTA method
- platform: web_server # Add this for web-based OTA uploads