fix: respect `repository.directory` for package repo links

app/pages/package/[...name].vue

···
 <script setup lang="ts">
+import { joinURL } from 'ufo'
 import type { PackumentVersion, NpmVersionDist } from '#shared/types'
 
 const route = useRoute('package-name')
···
 const repositoryUrl = computed(() => {
   const repo = displayVersion.value?.repository
   if (!repo?.url) return null
-  return normalizeGitUrl(repo.url)
+  let url = normalizeGitUrl(repo.url)
+  // append `repository.directory` for monorepo packages
+  if (repo.directory) {
+    url = joinURL(`${url}/tree/HEAD`, repo.directory)
+  }
+  return url
 })
 
 const homepageUrl = computed(() => {