feat(admin): open controller-link settings entries from the settings index

A settings entry with a controller opens that controller's route from
its card (settingsPath); singleton cards still open /settings/<code>.
On a linked controller with no navigation entry of its own the rail
marks Settings current, the breadcrumbs read Settings > entry label
(plus the record title on record and create routes) and the page title
uses the entry label. The settings docs describe the admin behaviour;
the embedded admin shell is rebuilt.

admin/src/components/shell/Breadcrumbs.vue

@@ -6,12 +6,14 @@ import { controllerIdFromPath, controllerPath } from '../../app/controllerRoutes
 import { t } from '../../app/i18n'
 import { recordCrumb } from '../../state/useBreadcrumbs'
 import { activeEntry, firstControllerPath } from '../../state/useNavigation'
-import { settingsEntry } from '../../state/useSettings'
+import { settingsEntry, settingsLinkFor, settingsPath } from '../../state/useSettings'
 
 // Header breadcrumbs (design: Top header): plugin, controller and record
 // labels, e.g. "Demo › Widgets › Blue widget". Parent crumbs are muted
 // links; the current crumb uses the text colour at 600 with
-// aria-current="page". Separators are 14px chevron-right icons.
+// aria-current="page". Separators are 14px chevron-right icons. A controller
+// opened from a settings link entry, with no navigation entry of its own,
+// reads "Settings › <entry label>".
 interface Crumb {
   label: string
   to?: string
@@ -29,11 +31,22 @@ const crumbs = computed<Crumb[]>(() => {
     return out
   }
   const plugin = activeEntry(String(route.params.vendor ?? ''), String(route.params.plugin ?? ''))
+  const id = controllerIdFromPath(route.path)
   if (!plugin) {
-    return []
+    const link = settingsLinkFor(id)
+    if (!link) {
+      return []
+    }
+    const out: Crumb[] = [
+      { label: t('backend::lang.nav.settings'), to: '/settings' },
+      { label: link.label, to: settingsPath(link) },
+    ]
+    if ((route.name === 'record' || route.name === 'create') && recordCrumb.value !== '') {
+      out.push({ label: recordCrumb.value })
+    }
+    return out
   }
   const out: Crumb[] = [{ label: plugin.label, to: firstControllerPath(plugin) ?? undefined }]
-  const id = controllerIdFromPath(route.path)
   const section = plugin.sideMenu.find((item) => item.controller === id) ?? null
   if (section) {
     out.push({ label: section.label, to: controllerPath(section.controller) ?? undefined })

admin/src/components/shell/PluginRail.vue

@@ -3,9 +3,10 @@ import { computed, nextTick, onBeforeUnmount, ref, watch } from 'vue'
 import { RouterLink, useRoute } from 'vue-router'
 import { PanelLeftOpen, Settings, Sun } from '@lucide/vue'
 import { t } from '../../app/i18n'
+import { controllerIdFromPath } from '../../app/controllerRoutes'
 import { iconFor } from '../../app/icons'
 import { activeEntry, firstControllerPath, railEntries } from '../../state/useNavigation'
-import { hasSettings } from '../../state/useSettings'
+import { hasSettings, settingsLinkFor } from '../../state/useSettings'
 import { useSidebar } from '../../state/useSidebar'
 import SectionFlyout from './SectionFlyout.vue'
 
@@ -25,8 +26,15 @@ const { collapsed, narrow, setCollapsed } = useSidebar()
 const active = computed(() => activeEntry(String(route.params.vendor ?? ''), String(route.params.plugin ?? '')))
 
 // Ustawienia (D-21) is pinned to the bottom and shown only when the admin may
-// manage at least one settings page.
-const inSettings = computed(() => route.path === '/settings' || route.path.startsWith('/settings/'))
+// manage at least one settings page. It is also current on a controller a
+// settings entry links to, unless that controller has its own navigation
+// entry (then its plugin stays highlighted).
+const inSettings = computed(
+  () =>
+    route.path === '/settings' ||
+    route.path.startsWith('/settings/') ||
+    (active.value === null && settingsLinkFor(controllerIdFromPath(route.path)) !== null),
+)
 
 const items = computed(() =>
   railEntries.value.map((entry) => ({