feat(content): demo the state engine (generator unlocks/lights the cellar)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Semesterprojekt/src/main/resources/world/items.yaml

@@ -22,3 +22,15 @@
   id: key
   name: Brass Key
   description: A small brass key, polished from use.
+
+- type: switchable
+  id: generator
+  name: Generator
+  description: A rusty generator with a heavy lever.
+  initialState: false
+  onText: |
+    You heave the lever. Somewhere deep in the manor, the lights flicker on.
+  offText: |
+    You pull the lever back; the manor falls dark again.
+  effects:
+    - { setFlag: power_on }

Semesterprojekt/src/main/resources/world/npcs.yaml

@@ -10,3 +10,8 @@
         "Thank you! Here, take this key."
       gives: key
       consumes: lamp
+  dialogue:
+    - when: [{ flag: power_on }]
+      text: |
+        "You got the power running! The whole house feels less...
+        watchful now."

Semesterprojekt/src/main/resources/world/rooms.yaml

@@ -9,6 +9,11 @@
     south: dungeon
   items: [letter, lamp]
   npcs: [old_man]
+  exitLocks:
+    - direction: east
+      requires: [{ flag: power_on }]
+      blocked: |
+        The cellar door is held shut by a magnetic lock — dead without power.
 
 - id: hallway
   name: Dark Hallway
@@ -40,12 +45,17 @@
     west: kitchen
   items: []
   npcs: []
+  descriptionStates:
+    - when: [{ flag: power_on }]
+      text: |
+        With the power back, a bare bulb buzzes overhead, revealing
+        shelves of dusty jars along the far wall.
 
 - id: dungeon
   name: Dungeon
   description: |
-    A dark, damp room.
+    A dark, damp room. A rusty generator squats in the corner.
   exits:
     north: kitchen
-  items: []
+  items: [generator]
   npcs: []