fix(17): WR-07 open a singleton's record from its list route

A settings link to a singleton controller only worked on a plain left
click; a new tab landed on the list route, which answers 404, and every
non-singleton link paid an extra /singleton request. The settings index
now links like any controller link, and the list view opens the
controller's one record when its list answers 404 and the singleton
route answers an id.

admin/src/views/ListView.vue

@@ -31,7 +31,9 @@ import { showToast } from '../state/useToasts'
 // A restored query the admin did not ask for never breaks the list: if its
 // load fails for any reason, the stored query is forgotten and the plain list
 // loads once instead (WR-02). A failed URL query keeps the error, with a reset
-// back to the plain list next to it.
+// back to the plain list next to it. A singleton controller (D-11) has no
+// list: its list route answers 404, and the view opens the controller's one
+// record instead (a settings link opened in a new tab, a bookmark).
 const SEARCH_DEBOUNCE = 300
 
 const route = useRoute()
@@ -176,6 +178,10 @@ async function loadList(restored = false): Promise<void> {
     void router.replace({ path: route.path, query: {} })
     return
   }
+  if (!result?.data && result?.response?.status === 404 && (await openSingleton(current))) {
+    // Keeps loading while the record opens; no error flashes.
+    return
+  }
   rows.value = result?.data?.data ?? []
   meta.value = result?.data?.meta ?? null
   listFailed.value = !result?.data
@@ -192,6 +198,27 @@ async function loadList(restored = false): Promise<void> {
   }
 }
 
+/**
+ * Opens the one record of a singleton controller (D-11) in place of its list,
+ * which answers 404. Reports whether it took over: false when the controller
+ * is not a singleton (its 404 stands).
+ */
+async function openSingleton(current: number): Promise<boolean> {
+  try {
+    const { data } = await api.GET('/{vendor}/{plugin}/{controller}/singleton', { params: { path } })
+    if (current !== generation) {
+      return true
+    }
+    if (!data) {
+      return false
+    }
+    await router.replace(`${basePath}/${data.data.id}`)
+    return true
+  } catch {
+    return false
+  }
+}
+
 function fetchList() {
   return api.GET('/{vendor}/{plugin}/{controller}', { params: { path, query: query.value } })
 }

admin/src/views/SettingsIndexView.vue

@@ -1,9 +1,5 @@
 <script setup lang="ts">
-import { ref } from 'vue'
-import { RouterLink, useRouter } from 'vue-router'
-import { api } from '../api/client'
-import type { SettingsEntry } from '../api/types'
-import { parseControllerId } from '../app/controllerRoutes'
+import { RouterLink } from 'vue-router'
 import { t } from '../app/i18n'
 import { iconFor } from '../app/icons'
 import { settingsGroups, settingsPath } from '../state/useSettings'
@@ -11,37 +7,10 @@ import { settingsGroups, settingsPath } from '../state/useSettings'
 // Settings index (D-21): every permitted settings page, grouped by category,
 // with its icon, label and description. The server filters the list. A
 // singleton entry opens its settings form; a link entry opens its controller.
-// A link to a singleton controller (D-11) opens that controller's one record:
-// GET …/singleton answers its id (a controller that is not a singleton
-// answers 404 and the link opens its list).
-const router = useRouter()
-const opening = ref<string | null>(null)
-
-async function open(event: MouseEvent, entry: SettingsEntry, navigate: (event: MouseEvent) => unknown): Promise<void> {
-  const params = entry.controller ? parseControllerId(entry.controller) : null
-  if (!params) {
-    void navigate(event)
-    return
-  }
-  if (event.button !== 0 || event.metaKey || event.ctrlKey || event.shiftKey || event.altKey) {
-    // A new tab or window opens the link as it is.
-    return
-  }
-  event.preventDefault()
-  if (opening.value !== null) {
-    return
-  }
-  opening.value = entry.code
-  const target = settingsPath(entry)
-  try {
-    const { data } = await api.GET('/{vendor}/{plugin}/{controller}/singleton', { params: { path: params } })
-    await router.push(data ? `${target}/${data.data.id}` : target)
-  } catch {
-    await router.push(target)
-  } finally {
-    opening.value = null
-  }
-}
+// A link to a singleton controller (D-11) points at the controller's list
+// route like any other, so a click, a new tab and a bookmark behave the
+// same; the list view opens the controller's one record when the list
+// answers 404 (ListView openSingleton).
 </script>
 
 <template>
@@ -70,9 +39,8 @@ async function open(event: MouseEvent, entry: SettingsEntry, navigate: (event: M
           <a
             :href="href"
             :data-settings="entry.code"
-            :aria-busy="opening === entry.code ? 'true' : undefined"
             class="flex items-start gap-3.5 rounded-card border border-border bg-surface p-5 text-text no-underline shadow-card hover:bg-hover"
-            @click="open($event, entry, navigate)"
+            @click="navigate"
           >
             <span class="flex size-10 shrink-0 items-center justify-center rounded-inner bg-subtle text-muted">
               <component :is="iconFor(entry.icon)" :size="20" aria-hidden="true" />