fix: stop unregistering Select item labels on unmount

SelectItem removed its entry from the shared itemLabels map on
unmount, which fires for every item when the dropdown closes --
including the item that was just selected. That wiped the trigger's
display label right after selecting (and after Escape/close in
general). Labels only need to be learned once and can safely persist,
matching the documented behavior in tests/Select.spec.ts. Found via
manual Storybook verification.

packages/library/src/components/ui/select/Select.vue

@@ -37,7 +37,6 @@ provide(SelectContextKey, {
   contentId: `select-content-${useId()}`,
   itemLabels,
   registerLabel: (value: string, label: string) => { itemLabels.set(value, label) },
-  unregisterLabel: (value: string) => { itemLabels.delete(value) },
 })
 </script>
 

packages/library/src/components/ui/select/SelectItem.vue

@@ -1,7 +1,7 @@
 <script setup lang="ts">
 import { CheckIcon } from '@lucide/vue'
 import type { HTMLAttributes } from 'vue'
-import { computed, inject, onBeforeUnmount, onMounted, ref } from 'vue'
+import { computed, inject, onMounted, ref } from 'vue'
 import { cn } from '@/lib/utils'
 import { SelectContextKey } from './context'
 import SelectItemText from './SelectItemText.vue'
@@ -31,9 +31,6 @@ function onPointerMove() {
 onMounted(() => {
   context.registerLabel(props.value, itemRef.value?.textContent?.trim() ?? '')
 })
-onBeforeUnmount(() => {
-  context.unregisterLabel(props.value)
-})
 </script>
 
 <template>

packages/library/src/components/ui/select/context.ts

@@ -8,7 +8,6 @@ export interface SelectContext {
   contentId: string
   itemLabels: Map<string, string>
   registerLabel: (value: string, label: string) => void
-  unregisterLabel: (value: string) => void
 }
 
 export const SelectContextKey: InjectionKey<SelectContext> = Symbol('SelectContext')