Add Option to Disable Payload Signing for AWS Lattice Compatibility

[SfinxCZ]

Hello,

First, thank you for maintaining this library — it's been incredibly helpful.

This pull request introduces an option to disable payload signing. This feature is required for compatibility with the AWS VPC Lattice service, which does not support payload signing, as outlined in the official documentation.

Could you please review this change and consider merging it if everything looks good?

Thank you!

[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
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0.0% Coverage on New Code
0.0% Duplication on New Code

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