Convert api-fetch package to TypeScript

[manzoorwanijk]

Fixes #59087

What?

• Convert api-fetch package to TypeScript
• Improve types for API fetch to return dynamic value based on parse option
• Convert the corresponding unit tests to TS
• Expose apiFetch as named export

Why?

Improve the DX and fix an issue when used in ES Modules

How?

By renaming the files and updating types

Testing Instructions

• CI should be happy

[github-actions]

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Co-authored-by: gziolo <[email protected]>
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[gziolo]

Moved to #67669.