fix(s3-deployment): handle properly quoted strings in JSON files

The S3 deployment custom resource now properly handles strings containing quotes
when used in JSON files, while maintaining the existing behavior for other file
types including YAML files.

Changes:
- Added JSON detection and special handling in the Lambda custom resource
- Added integration tests for both JSON and YAML files with quoted values
- Added bucket cleanup configuration to the test stack

Test cases show that:
- JSON files properly escape quotes: {"secret_value": "test\"with\"quotes"}
- YAML files work as-is: secret_value: test"with"quotes