Scope

What's changed:

• Fixed the error case of search: undefined actually searching for the string 'undefined' (linked issue)
• Fixed undefined handling for the other query parameters
• Attempted to make the query formatting conditions more explicit
• Added tests for the formatFields and queryToParams utilities
• Fixed the aggregate type by adding Partial (the tests showed that all aggregation keys were required before)
• Fixed the aggregate type by adding & Record<string, unknown> allowing for custom properties without type errors
• Moved the request.test.ts file next to the request.ts file (to consistently keep functional test files next to the file they're testing and type tests in the test/ folder)

Potential Risks / Drawbacks

• Something could break if relying on the old fall-through into custom parameter logic for "knownQueryKeys". I covered the edge cases I could think of with explicit logic to handle them.

Tested Scenarios

• See the added test file

Review Notes / Questions

• Did I miss any edge cases in the tests?

Checklist

• Added or updated tests

Fixes #25930