What problems was I solving

The ExtractPathParams<T extends string> type alias in api-builder/main/types/path-inference.ts was an unused wrapper around ExtractPathParamsFromString<T>. It was never barrel-exported, never imported by other modules, and had no consumers, so it added unnecessary surface area to the path-inference types.

What user-facing changes did I ship

There are no user-facing changes. The public ExtractPathParamsFromString type continues to work exactly as before.

How I implemented it

Removed the three-line alias and kept the existing ExtractPathParamsFromString<T> definition and public export intact. No other code, tests, or exports were modified.

Description for the changelog

Removed the unused ExtractPathParams<T extends string> type alias from api-builder/main/types/path-inference.ts. The public ExtractPathParamsFromString<T> type and its barrel export remain unchanged, so there is no impact on consumers or the generated API surface.