docs(appsync): rewrite and split async resolvers

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 18-19 21 28"
+    ```python hl_lines="4 10 20-21 23 30"
     --8<-- "examples/event_handler_graphql/src/nested_mappings.py"
     ```
 
@@ -122,28 +122,8 @@ You can nest `app.resolver()` decorator multiple times when resolving fields wit
 
 For Lambda Python3.8+ runtime, this utility supports async functions when you use in conjunction with `asyncio.run`.
 
-```python hl_lines="5 9 11-13 21" title="Resolving GraphQL resolvers async"
-import asyncio
-from aws_lambda_powertools import Logger, Tracer
-
-from aws_lambda_powertools.logging import correlation_paths
-from aws_lambda_powertools.event_handler import AppSyncResolver
-
-tracer = Tracer(service="sample_resolver")
-logger = Logger(service="sample_resolver")
-app = AppSyncResolver()
-
-@app.resolver(type_name="Query", field_name="listTodos")
-async def list_todos():
-	todos = await some_async_io_call()
-	return todos
-
-@logger.inject_lambda_context(correlation_id_path=correlation_paths.APPSYNC_RESOLVER)
-@tracer.capture_lambda_handler
-def lambda_handler(event, context):
-	result = app.resolve(event, context)
-
-	return asyncio.run(result)
+```python hl_lines="7 14 24-25 34 36" title="Resolving GraphQL resolvers async"
+--8<-- "examples/event_handler_graphql/src/async_resolvers.py"
 ```
 
 ### Amplify GraphQL Transformer

examples/event_handler_graphql/src/async_resolvers.py

@@ -0,0 +1,36 @@
+import asyncio
+from typing import TypedDict
+
+import aiohttp
+
+from aws_lambda_powertools import Logger, Tracer
+from aws_lambda_powertools.event_handler import AppSyncResolver
+from aws_lambda_powertools.logging import correlation_paths
+from aws_lambda_powertools.tracing import aiohttp_trace_config
+from aws_lambda_powertools.utilities.typing import LambdaContext
+
+tracer = Tracer()
+logger = Logger()
+app = AppSyncResolver()
+
+
+class Todo(TypedDict):
+    id: str  # noqa AA03 VNE003, required due to GraphQL Schema
+    userId: str
+    title: str
+    completed: bool
+
+
+@app.resolver(type_name="Query", field_name="listTodos")
+async def list_todos() -> list[Todo]:
+    async with aiohttp.ClientSession(trace_configs=[aiohttp_trace_config()]) as session:
+        async with session.get("https://jsonplaceholder.typicode.com/todos") as resp:
+            return await resp.json()
+
+
+@logger.inject_lambda_context(correlation_id_path=correlation_paths.APPSYNC_RESOLVER)
+@tracer.capture_lambda_handler
+def lambda_handler(event: dict, context: LambdaContext) -> dict:
+    result = app.resolve(event, context)
+
+    return asyncio.run(result)