Revert "fix(types): correct withDefaults return type for boolean prop with undefined default value (vuejs#8602)"

This reverts commit f07cb18.

Author: zhangenming

packages/dts-test/setupHelpers.test-d.ts

@@ -134,26 +134,6 @@ describe('defineProps w/ generic type declaration + withDefaults', <T extends nu
   expectType<boolean>(res.bool)
 })
 
-describe('withDefaults w/ boolean type', () => {
-  const res1 = withDefaults(
-    defineProps<{
-      bool?: boolean
-    }>(),
-    { bool: false }
-  )
-  expectType<boolean>(res1.bool)
-
-  const res2 = withDefaults(
-    defineProps<{
-      bool?: boolean
-    }>(),
-    {
-      bool: undefined
-    }
-  )
-  expectType<boolean | undefined>(res2.bool)
-})
-
 describe('defineProps w/ runtime declaration', () => {
   // runtime declaration
   const props = defineProps({

packages/runtime-core/src/apiSetupHelpers.ts

@@ -303,13 +303,7 @@ type PropsWithDefaults<
       ? T[K]
       : NotUndefined<T[K]>
     : never
-} & {
-  readonly [K in BKeys]-?: K extends keyof Defaults
-    ? Defaults[K] extends undefined
-      ? boolean | undefined
-      : boolean
-    : boolean
-}
+} & { readonly [K in BKeys]-?: boolean }
 
 /**
  * Vue `<script setup>` compiler macro for providing props default values when