feat(cabana): read-only Plugins screen with installed plugins

- GET /plugins (backend.view_plugins, superusers always pass) lists the
  plugins from party.Installed, or party.Activated IDs for older builds,
  with the built framework version and whether the registry is configured
- Settings -> System -> Plugins entry with the new SettingsEntry.path,
  added only for principals allowed to open it
- PluginsView at /system/plugins with an Installed tab (reka-ui Tabs);
  settings panel, rail, breadcrumbs and page title know the route
- OpenAPI and SPA types regenerated; contract, token-class and
  conformance inventories list the route; en/pl strings; docs

admin/tests/fixtures/lang.json

@@ -645,6 +645,57 @@
     "backend::lang.page.not_found": {
       "other": "Nie znaleziono strony."
     },
+    "backend::lang.permissions.view_plugins": {
+      "other": "Podgląd wtyczek"
+    },
+    "backend::lang.plugins.column_plugin": {
+      "other": "Wtyczka"
+    },
+    "backend::lang.plugins.column_source": {
+      "other": "Źródło"
+    },
+    "backend::lang.plugins.column_version": {
+      "other": "Wersja"
+    },
+    "backend::lang.plugins.empty": {
+      "other": "Brak zainstalowanych wtyczek."
+    },
+    "backend::lang.plugins.framework": {
+      "other": "Framework :version"
+    },
+    "backend::lang.plugins.load_failed": {
+      "other": "Nie udało się wczytać listy wtyczek."
+    },
+    "backend::lang.plugins.menu_description": {
+      "other": "Zainstalowane wtyczki, ich wersje i dostępne aktualizacje oraz katalog wtyczek."
+    },
+    "backend::lang.plugins.menu_label": {
+      "other": "Wtyczki"
+    },
+    "backend::lang.plugins.no_version": {
+      "other": "Brak wersji"
+    },
+    "backend::lang.plugins.source_local": {
+      "other": "W aplikacji"
+    },
+    "backend::lang.plugins.source_module": {
+      "other": "Moduł Go"
+    },
+    "backend::lang.plugins.source_submodule": {
+      "other": "Submoduł git"
+    },
+    "backend::lang.plugins.tab_installed": {
+      "other": "Zainstalowane"
+    },
+    "backend::lang.plugins.tab_marketplace": {
+      "other": "Katalog"
+    },
+    "backend::lang.plugins.tabs_label": {
+      "other": "Sekcje ekranu Wtyczki"
+    },
+    "backend::lang.plugins.title": {
+      "other": "Wtyczki"
+    },
     "backend::lang.relation.add": {
       "other": "Dodaj"
     },

admin/tests/views/PluginsView.test.ts

@@ -0,0 +1,110 @@
+import { afterEach, beforeEach, describe, expect, it } from 'vitest'
+import { enableAutoUnmount } from '@vue/test-utils'
+import PluginsView from '../../src/views/PluginsView.vue'
+import { settingsPath } from '../../src/state/useSettings'
+import type { InstalledPlugin, PluginsOverview, SettingsEntry } from '../../src/api/types'
+import { API, mountApp, requestsTo, resetState, type Route } from '../helpers'
+
+const PLUGINS = `${API}/plugins`
+
+function installed(overrides: Partial<InstalledPlugin> & { id: string }): InstalledPlugin {
+  return {
+    name: '',
+    description: '',
+    version: '',
+    source: '',
+    module: '',
+    package: '',
+    listed: false,
+    latest: '',
+    latestFramework: '',
+    updateAvailable: false,
+    updateCommand: '',
+    ...overrides,
+  }
+}
+
+function overview(overrides: Partial<PluginsOverview> = {}): PluginsOverview {
+  return {
+    framework: 'v0.6.0',
+    registry: { enabled: false, status: 'disabled' },
+    plugins: [
+      installed({
+        id: 'acme.blog',
+        name: 'Blog',
+        description: 'Posts <b>and</b> categories.',
+        version: 'v0.1.0',
+        source: 'module',
+        module: 'example.test/acme-blog',
+        package: 'example.test/acme-blog',
+      }),
+      installed({ id: 'acme.local', source: 'local' }),
+    ],
+    ...overrides,
+  }
+}
+
+const envelope = (data: unknown) => ({ body: { data, meta: {} } })
+
+async function openPlugins(data: PluginsOverview = overview(), routes: Record<string, Route> = {}) {
+  return mountApp('/system/plugins', { [`GET ${PLUGINS}`]: envelope(data), ...routes }, { attach: true })
+}
+
+beforeEach(() => {
+  resetState()
+})
+
+afterEach(() => {
+  document.body.innerHTML = ''
+})
+
+enableAutoUnmount(afterEach)
+
+describe('PluginsView', () => {
+  it('renders the installed plugins from GET /plugins', async () => {
+    const { wrapper, calls } = await openPlugins()
+    expect(wrapper.findComponent(PluginsView).exists()).toBe(true)
+    expect(requestsTo(calls, 'GET', PLUGINS)).toHaveLength(1)
+    expect(wrapper.find('h1').text()).toBe('Wtyczki')
+    expect(wrapper.find('[data-plugins-framework]').text()).toBe('Framework v0.6.0')
+
+    const rows = wrapper.findAll('[data-plugin]')
+    expect(rows.map((row) => row.attributes('data-plugin'))).toEqual(['acme.blog', 'acme.local'])
+    const blog = rows[0]!
+    expect(blog.find('[data-plugin-name]').text()).toBe('Blog')
+    expect(blog.find('[data-plugin-version]').text()).toBe('v0.1.0')
+    expect(blog.find('[data-plugin-source]').text()).toBe('Moduł Go')
+    // Registry and plugin text is text, never HTML.
+    expect(blog.find('[data-plugin-description]').text()).toBe('Posts <b>and</b> categories.')
+    expect(blog.find('b').exists()).toBe(false)
+
+    const local = rows[1]!
+    expect(local.find('[data-plugin-name]').text()).toBe('acme.local')
+    expect(local.find('[data-plugin-version]').text()).toBe('Brak wersji')
+    expect(local.find('[data-plugin-source]').text()).toBe('W aplikacji')
+  })
+
+  it('shows an error when the list cannot be loaded', async () => {
+    const { wrapper } = await openPlugins(overview(), {
+      [`GET ${PLUGINS}`]: { status: 403, body: { error: { code: 'forbidden', message: 'Forbidden', details: {} } } },
+    })
+    expect(wrapper.find('[data-plugins-failed]').exists()).toBe(true)
+    expect(wrapper.findAll('[data-plugin]')).toHaveLength(0)
+  })
+
+  it('opens from the settings entry path', () => {
+    const entry: SettingsEntry = {
+      code: 'plugins',
+      label: 'Wtyczki',
+      description: '',
+      category: 'System',
+      icon: 'puzzle',
+      order: 120,
+      keywords: [],
+      model: '',
+      controller: '',
+      path: '/system/plugins',
+    }
+    expect(settingsPath(entry)).toBe('/system/plugins')
+  })
+})