fix: make SpecificResponseType correctly find fallbacks

Author: nlf

lib/types.ts

@@ -125,16 +125,29 @@ export type ResponseType<R extends Route> = R["settings"]["response"];
 export type BodyType<R extends Route> = "body" extends keyof R["settings"]["response"]
   ? R["settings"]["response"]["body"]
   : unknown;
+
+type MoreThanOne<T, Td = T> = T extends unknown
+  ? [Td] extends [T]
+      ? never
+      : T
+  : never;
+
+type FallbackStatus<T> = "status" extends keyof T
+  ? T extends { status: MoreThanOne<T["status"]> }
+    ? T
+    : never
+  : never;
+
 /**
  * Get the response type for a route matching a specific status code
  */
-export type SpecificResponseType<R extends Route, S extends StatusCode = StatusCode> = R["settings"]["response"] extends { status: S }
-  ? R["settings"]["response"]
-  : "status" extends keyof R["settings"]["response"]
-    ? S extends R["settings"]["response"]["status"]
-      ? R["settings"]["response"]
-      : RouteSettings["response"]
-    : RouteSettings["response"];
+export type SpecificResponseType<
+  R extends Route,
+  S extends StatusCode = StatusCode,
+  Ex = Extract<R["settings"]["response"], { status: S }>,
+> = Extract<R["settings"]["response"], { status: S }> extends never
+  ? FallbackStatus<R["settings"]["response"]>
+  : Ex;
 /**
  * Get the response body type for a route matching a specific status code
  */