T04.f: backend Festipod ActivityPods + dockerisation

- Ajoute la configuration et les services backend (app, actors, registration,
  attendees, contacts, catalog, core auth/nodeinfo/proxy/notification).
- Corrige le démarrage : désactive resourcesWithContainerPath pour éviter le
  conflit entre l'URI de l'acteur applicatif (/as/actor/app) et la route /app.
- Corrige l'URL du dépôt de shapes : https://shapes.activitypods.org/.
- Ajoute backend/Dockerfile et docker-compose.yml racine (frontend + backend).
- Met à jour .env.example racine avec les variables SEMAPPS_* et VITE_BACKEND_*.
- Gates verts : bunx tsc --noEmit (0 erreur) et bun test (50 pass).

backend/services/app.service.js

@@ -0,0 +1,51 @@
+const urlJoin = require('url-join');
+const { AppService } = require('@activitypods/app');
+const CONFIG = require('../config/config');
+
+module.exports = {
+  mixins: [AppService],
+  settings: {
+    baseUrl: CONFIG.HOME_URL,
+    app: {
+      name: CONFIG.APP_NAME,
+      description: CONFIG.APP_DESCRIPTION,
+      thumbnail: urlJoin(CONFIG.FRONT_URL, 'logo.svg'),
+      frontUrl: CONFIG.FRONT_URL,
+      supportedLocales: CONFIG.APP_LANG
+    },
+    oidc: {
+      clientUri: CONFIG.FRONT_URL,
+      redirectUris: urlJoin(CONFIG.FRONT_URL, 'login'),
+      postLogoutRedirectUris: urlJoin(CONFIG.FRONT_URL, 'login?logout=true'),
+      tosUri: null
+    },
+    accessNeeds: {
+      required: [
+        {
+          shapeTreeUri: urlJoin(CONFIG.SHAPE_REPOSITORY_URL, 'shapetrees/as/Event'),
+          accessMode: ['acl:Read', 'acl:Write', 'acl:Control'],
+          preferredScope: 'interop:AllFromRegistry'
+        },
+        {
+          shapeTreeUri: urlJoin(CONFIG.SHAPE_REPOSITORY_URL, 'shapetrees/as/Profile'),
+          accessMode: ['acl:Read', 'acl:Write'],
+          preferredScope: 'interop:AllFromRegistry'
+        },
+        {
+          shapeTreeUri: urlJoin(CONFIG.SHAPE_REPOSITORY_URL, 'shapetrees/vcard/Group'),
+          accessMode: 'acl:Read',
+          preferredScope: 'interop:AllFromRegistry'
+        },
+        'apods:ReadInbox',
+        'apods:ReadOutbox',
+        'apods:PostOutbox',
+        'apods:QuerySparqlEndpoint',
+        'apods:CreateWacGroup',
+        'apods:CreateCollection',
+        'apods:UpdateWebId'
+      ],
+      optional: []
+    },
+    queueServiceUrl: CONFIG.QUEUE_SERVICE_URL
+  }
+};