Update default value for Terraform MCP Server integration

[becojo]

#2101 #2103

Changed default value for terraform.mcp.server.enable from true to false.

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• I have documented a clear reason for, and description of, the change I am making.
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[dduzgun-security]

✅ from team-prodsec, we should disable this option by default.
Thanks @becojo for the PR.

edit after triggering the pipeline: I believe the only thing that is missing to make the CI checks happy is a changelog entry in .changes/unreleased

[anubhav-goel]

Looks great! Could you please add a new changelog entry for this? You can generate it by running changie new and following the prompts. Thanks!

[magnetikonline]

Great decision - I didn't appreciate an MCP server image magically appearing in my local docker set of images. 👍

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