feat: add category fields for BME.

- add category for BME prorotypes.
- update validator and extractor for this change.

assets/jsons/terminals.json5

@@ -77,6 +77,7 @@
         "identifier": "floor_normal_terminal",
         "showcase": {
             "title": "Normal Floor Terminal",
+            "category": "Floors",
             "icon": "NormalFloorTerminal",
             "type": "floor",
             "cfgs": [
@@ -127,6 +128,7 @@
         "identifier": "floor_sink_terminal",
         "showcase": {
             "title": "Sink Floor Terminal",
+            "category": "Floors",
             "icon": "SinkFloorTerminal",
             "type": "floor",
             "cfgs": [