docs(examples): add SAM example for large-messages module

[sasanchezramirez]

Summary

This PR introduces a comprehensive SAM example for the powertools-large-messages module. It demonstrates how to use the functional interface approach (LargeMessages.processLargeMessage) to handle SQS messages with offloaded S3 payloads, following the request in the linked issue.

Changes

• Created new module powertools-examples-large-messages under examples/.
• Added template.yaml configuring S3, SQS, and Lambda with correct IAM permissions (S3CrudPolicy).
• Implemented App.java demonstrating LargeMessages.processLargeMessage() usage (functional API).
• Configured pom.xml with the latest SQS Extended Client dependency.
• Added README.md with deployment and testing instructions.
• Added log4j2.xml resource for proper logging output.

Issue number: Closes #1353

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Documentation update
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• My code follows the code style of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• Changes generate no new warnings

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 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]

Hey @sasanchezramirez,

thanks for sending this PR. Very much appreciated.

I am at re:Invent this week and will review your PR next week.