Don't crash if a meta.json isn't provided

Author: silasary

src/Meta.py

@@ -20,6 +20,9 @@ class ManualWeb(WebWorld):
 # Convert meta.json data to properties
 ######################################
 def set_world_description(base_doc: str) -> str:
+    if meta_table.get("docs", {}).get("apworld_description", None) is None:
+        return base_doc
+
     if isinstance(meta_table["docs"]["apworld_description"], str):
         base_doc = meta_table["docs"]["apworld_description"]
     else:
@@ -68,4 +71,4 @@ def set_world_webworld(web: WebWorld) -> WebWorld:
     """)
 world_webworld: ManualWeb = set_world_webworld(ManualWeb())
 
-enable_region_diagram = bool(meta_table.get("enable_region_diagram", False))
+enable_region_diagram = bool(meta_table.get("enable_region_diagram", False))