fix: accept burden stats from plugin

main.py

@@ -1103,6 +1103,9 @@ class CharacterStatsMessage(BaseModel):
     birth: Optional[str] = None
     current_title: Optional[int] = None
     skill_credits: Optional[int] = None
+    burden: Optional[int] = None
+    burden_units: Optional[int] = None
+    encumbrance_capacity: Optional[int] = None
     attributes: Optional[dict] = None
     vitals: Optional[dict] = None
     skills: Optional[dict] = None
@@ -2479,6 +2482,9 @@ async def ws_receive_snapshots(
                         "birth",
                         "current_title",
                         "skill_credits",
+                        "burden",
+                        "burden_units",
+                        "encumbrance_capacity",
                         "properties",
                         "titles",
                     ):
@@ -2987,6 +2993,9 @@ async def test_character_stats(name: str):
             "birth",
             "current_title",
             "skill_credits",
+            "burden",
+            "burden_units",
+            "encumbrance_capacity",
         ):
             if stats_dict.get(key) is not None:
                 stats_data[key] = stats_dict[key]