fix(Calendar/InputMenu/Textarea): add missing PartialString type on ui prop

Resolves #3299

src/runtime/components/Textarea.vue

@@ -4,6 +4,7 @@ import type { AppConfig } from '@nuxt/schema'
 import _appConfig from '#build/app.config'
 import theme from '#build/ui/textarea'
 import { tv } from '../utils/tv'
+import type { PartialString } from '../types/utils'
 
 const appConfigTextarea = _appConfig as AppConfig & { ui: { textarea: Partial<typeof theme> } }
 
@@ -34,7 +35,7 @@ export interface TextareaProps {
   autoresize?: boolean
   /** Highlight the ring color like a focus state. */
   highlight?: boolean
-  ui?: Partial<typeof textarea.slots>
+  ui?: PartialString<typeof textarea.slots>
 }
 
 export interface TextareaEmits {