feat(entities): andamiatge del sistema d'entitats (classes, factory, bus, YAML, placeholders, smoke tests)

data/entities/sarcophagus/sarcophagus.yaml

@@ -0,0 +1,19 @@
+name: sarcophagus
+type: interactable
+sprite:
+  path: sarcophagus.gif
+  size: [48, 16]
+tile_size: [3, 1]
+flags:
+  collides: true
+  interactable: true
+animations:
+  closed:  { frames: [0], fps: 1, loop: true }
+  opening: { frames: [0], fps: 6, loop: false }
+  open:    { frames: [0], fps: 1, loop: true }
+behaviour:
+  states: [CLOSED, OPENING, OPEN]
+  initial_state: CLOSED
+  on_perimeter_complete: OPENING
+  on_opening_end: OPEN
+  emits_event_on_open: sarcophagus_opened