com.amazonaws.apigateway.request.context missing in backend @RestController

# Issue: `com.amazonaws.apigateway.request.context` missing in backend `@RestController`

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Serverless Java Container version: `2.1.4`

Implementations: Spring Boot 3

Framework version: SpringBoot `3.5.3`

Frontend service: REST API / API Gateway Proxy Request

Deployment method: SAM

## Description
When using **Spring Boot 3.5.3** with **aws-serverless-java-container-springboot3:2.1.4**,
the `AwsProxyRequestContext` is not being injected into a controller method when annotated with:

`@RequestAttribute("com.amazonaws.apigateway.request.context")`

This attribute is expected to contain the API Gateway request context, but instead it is always null.

## Lambda Handler
```
import com.amazonaws.serverless.exceptions.ContainerInitializationException;
import com.amazonaws.serverless.proxy.internal.LambdaContainerHandler;
import com.amazonaws.serverless.proxy.model.AwsProxyRequest;
import com.amazonaws.serverless.proxy.model.AwsProxyResponse;
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.RequestStreamHandler;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class LambdaHandler implements RequestStreamHandler {
private static final SpringBootLambdaContainerHandler handler;

static {
try {
handler = new SpringBootProxyHandlerBuilder()
.defaultProxy()
.initializationWrapper(new InitializationWrapper())
.springBootApplication(Application.class)
.buildAndInitialize();
} catch (ContainerInitializationException e) {
throw new LambdaException("Could not initialize Lambda. ", e);
}
}

@Override
public void handleRequest(InputStream inputStream, OutputStream outputStream, Context context) throws IOException {
handler.proxyStream(inputStream, outputStream, context);
}
}
```

## Controller
```
import com.amazonaws.serverless.proxy.model.AwsProxyRequestContext;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.Map;

@RestController
public class GeographicAddressController {

private static final String API_GATEWAY_CONTEXT_PROPERTY = "com.amazonaws.apigateway.request.context";

@GetMapping(path = "/geographicAddress", produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity get(
final @RequestHeader HttpHeaders reqHeaders,
final @RequestParam Map params,
final @RequestAttribute(value = API_GATEWAY_CONTEXT_PROPERTY, required = false) AwsProxyRequestContext requestContext
) {
// requestContext is always null, I would like to get AwsProxyRequestContext , and authorizer details
return ResponseEntity.ok().build();
}
}
```
## Expected Behavior
The `requestContext` parameter should be populated with the `AwsProxyRequestContext` extracted from the incoming API Gateway event.
## Actual Behavior
`requestContext` is always `null` inside the controller method.

## Steps to Reproduce

- Deploy a `Spring Boot 3.5.3` application with `aws-serverless-java-container-springboot3:2.1.4`.
- Use the Lambda handler shown above.
- Add a controller method with `@RequestAttribute("com.amazonaws.apigateway.request.context")`.
- Invoke the API Gateway endpoint.
- Observe that `requestContext` is always `null`.

Commencez par le point d’entrée LambdaHandler et GeographicAddressController présentés dans l’issue, puis suivez la manière dont le API Gateway request context est exposé aux attributs du contrôleur Spring. Reproduisez la requête avec les versions de Spring Boot et du conteneur indiquées ; le travail est terminé lorsque @RequestAttribute reçoit le AwsProxyRequestContext, y compris les détails de l’authorizer, au lieu de null.

Rédigé par le modèle d'indexation à partir du texte de l'issue.