fix(readme): replace JSON-RPC 2.0 with HTTP REST API for Unix socket description

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: JanZachmann

README.md

@@ -34,7 +34,7 @@ Depending on `MACHINE_FEATURES` we also set `3g`, `bluetooth` and `wifi`.
     - expands the data partition to available space on first boot
 - [`wifi-commissioning`](https://github.com/janzachmann/wifi-commissioning-service.git)
     - adds a service which enables wifi commissioning via BLE GATT and Unix socket
-    - provides Bluetooth Low Energy interface for initial commissioning and JSON-RPC 2.0 Unix socket for programmatic access
+    - provides Bluetooth Low Energy interface for initial commissioning and HTTP REST API over Unix socket for programmatic access
     - depends on `DISTRO_FEATURES` `wifi` and `bluetooth` which are not added to `DISTRO_FEATURES` automatically!
     - **note**: BLE interface is intended for demo/initial commissioning; Unix socket provides production-ready programmatic access