feat(lmds): Add support for Lambda Metadata Service

[phipag]

Summary

Adds powertools-lambda-metadata utility. Can be used to query LMDS endpoint on Lambda. Supports:

• Lambda Managed Instances thread-safety
• Caching of result
• Lazy loading on first request
• SnapStart hooks to invalidate cache on restore
• GraalVM supported

User experience

public class TriageHandler implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {

    private static final Logger logger = LoggerFactory.getLogger(TriageHandler.class);
    private static final Metrics metrics = MetricsFactory.getMetricsInstance();
    private static final LambdaMetadata METADATA = LambdaMetadataClient.get();

    @Logging(logEvent = true)
    @Tracing
    @FlushMetrics(namespace = "TriagingTemplate", service = "triage")
    public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent input, Context context) {
        logger.info("Processing triage request");
        logger.info("Metadata", StructuredArguments.entry("metadata", METADATA));
        logger.info("Metadata AZ ID {}", METADATA.getAvailabilityZoneId());
        logger.info("Environment variables", StructuredArguments.entries(System.getenv()));

        // Add custom metric
        metrics.addMetric("TriageRequests", 1, MetricUnit.COUNT);

        Map<String, String> headers = new HashMap<>();
        headers.put("Content-Type", "application/json");

        String responseBody = """
                {
                    "message": "Hello from Powertools Triaging Template!",
                    "service": "triage",
                    "version": "1.0.0"
                }
                """;

        logger.info("Triage request processed successfully");

        return new APIGatewayProxyResponseEvent()
                .withStatusCode(200)
                .withHeaders(headers)
                .withBody(responseBody);
    }
}

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
2 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[phipag]

E2E tests pass https://github.com/aws-powertools/powertools-lambda-java/actions/runs/23249609104