fix(tools): strip unsupported prefixItems from JSON schema to fix FunctionTool crash

Author: EaCognitive

src/google/adk/tools/_function_parameter_parse_util.py

@@ -131,7 +131,19 @@ def _generate_json_schema_for_parameter(
   json_schema_dict = _add_unevaluated_items_to_fixed_len_tuple_schema(
       json_schema_dict
   )
-  return json_schema_dict
+  
+  def _strip_unsupported_keys(d: Any) -> Any:
+      if isinstance(d, dict):
+          d.pop('prefixItems', None)
+          d.pop('unevaluatedItems', None)
+          for k, v in d.items():
+              _strip_unsupported_keys(v)
+      elif isinstance(d, list):
+          for item in d:
+              _strip_unsupported_keys(item)
+      return d
+
+  return _strip_unsupported_keys(json_schema_dict)
 
 
 def _is_builtin_primitive_or_compound(