docs(appsync): improve typing and tracing for nested mappings snippet

Author: heitorlessa

docs/core/event_handler/appsync.md

@@ -108,7 +108,7 @@ You can nest `app.resolver()` decorator multiple times when resolving fields wit
 
 === "nested_mappings.py"
 
-    ```python hl_lines="2 8 11-12 14 21"
+    ```python hl_lines="2 8 18-19 21 28"
     --8<-- "examples/event_handler_graphql/src/nested_mappings.py"
     ```
 

examples/event_handler_graphql/src/nested_mappings.py

@@ -1,3 +1,5 @@
+from typing import TypedDict
+
 from aws_lambda_powertools import Logger, Tracer
 from aws_lambda_powertools.event_handler import AppSyncResolver
 from aws_lambda_powertools.logging import correlation_paths
@@ -8,11 +10,18 @@
 app = AppSyncResolver()
 
 
+class Location(TypedDict):
+    id: str  # noqa AA03 VNE003, required due to GraphQL Schema
+    name: str
+    description: str
+    address: str
+
+
 @app.resolver(field_name="listLocations")
 @app.resolver(field_name="locations")
 @tracer.capture_method
-def get_locations(name: str, description: str = ""):  # match GraphQL Query arguments
-    return name + description
+def get_locations(name: str, description: str = "") -> list[Location]:  # match GraphQL Query arguments
+    return [{"name": name, "description": description}]
 
 
 @logger.inject_lambda_context(correlation_id_path=correlation_paths.APPSYNC_RESOLVER)