clarify room and sensor

src/devices/sensor.jsonnet

@@ -15,6 +15,6 @@ entity
       items: types.id,
       description: 'List of variables measured by sensor.',
       uniqueItems: true,
-    }
-  }
+    },
+  },
 }

src/locations/room.jsonnet

@@ -12,15 +12,14 @@ entity
   properties+: {
     location: types.location,
     relationships: {
-      type: 'array',
+      type: 'object',
       description: 'Relationships that bind other entities to this room.',
-      items: {
-        oneOf: [
-          {
-            '$ref': 'https://picc.app/schemata/v0.1-dev/relationship',
+      properties: {
+        id: type.id,
+        args: {
+          type: 'array',
+          items: type.id,
         },
-          $.properties.id,
-        ],
       },
     },
   },