feat: add headers case preserve

[ahbonsu]

Purpose

Add a config property to configuration catalog that allows preserving header key capitalization

Issues

Fixes #3621

Automation tests

• Unit tests added: Yes
• Integration tests added: No

Tested environments

local testing on debian 12, default container image alpine 3.19.4, go 1.22.7

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Maintainers: Check before merge

• Assigned 'Type' label
• Assigned the project
• Validated respective github issues
• Assigned milestone to the github issue(s)

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