[BUG][TypeScript] Fixed TypeScript code generation for oneOf using arrays

[psegalen]

This PR just fixes the syntax of the generated code, no opinionated new code, no change of any nature to anything, just some syntax fix.
It fixes issue #22779

Fix is only about balancing unbalanced parentheses and using the correct variables, nothing else.

Again, as this doesn't change anything about anything already functional and being in a kind of a hurry, I haven't walked through the PR checklist, sorry.

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Summary by cubic

Fixed TypeScript code generation for oneOf arrays so Date and DateTime arrays parse and serialize correctly. This corrects variable usage and missing parentheses in the template.

• Bug Fixes
  • Use item (not json) in json.every and map.
  • Balance missing parentheses in if conditions and map calls.
  • Map to new Date(value) when parsing arrays; serialize Date arrays with toISOString().substring(0,10) and DateTime arrays with item.toISOString().

^{Written for commit 785ecb4. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 1 file

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