fix(golang): use datatype only for enums instead of format

[rubenhoenle]

relates to #24336

Detailed description and steps to reproduce can be found in the linked GitHub issue.

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---

Summary by cubic

Fixes Go enum generation when a schema sets format: "enum" by always using the base data type in generated enums. Prevents invalid types in both models and properties.

• Bug Fixes
  • Updated go/model_enum.mustache to use {{dataType}} for the enum type, the UnmarshalJSON value, and the NewXFromValue parameter, removing reliance on {{format}}.

^{Written for commit 3a44bf6. Summary will update on new commits.}

[rubenhoenle]

See the linked GitHub issue for context of the latest change to this PR.

[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}