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/moleculer.config.js

@@ -0,0 +1,62 @@
+const { CacherMiddleware } = require('@semapps/webacl');
+const CONFIG = require('./config/config');
+
+Error.stackTraceLimit = Infinity;
+
+const cacherConfig = CONFIG.REDIS_CACHE_URL
+  ? {
+      type: 'Redis',
+      options: {
+        prefix: 'action',
+        ttl: 2592000,
+        redis: CONFIG.REDIS_CACHE_URL
+      }
+    }
+  : undefined;
+
+const SkipOrphanBlankNodesCleanupMiddleware = () => ({
+  name: 'SkipOrphanBlankNodesCleanupMiddleware',
+  localAction: (next, action) => {
+    if (action.name === 'triplestore.deleteOrphanBlankNodes') {
+      return async () => {};
+    }
+    return next;
+  }
+});
+
+// ActivityPods app services mark internal calls with isSystemCall, but the SDK
+// triplestore layer needs an explicit webId='system' to bypass pod-side WAC.
+const SystemCallWebIdMiddleware = () => ({
+  name: 'SystemCallWebIdMiddleware',
+  localAction: (next, action) => {
+    return async ctx => {
+      if (ctx.meta?.isSystemCall && !ctx.params?.webId) {
+        ctx.params.webId = 'system';
+      }
+      return next(ctx);
+    };
+  }
+});
+
+module.exports = {
+  middlewares: [
+    SkipOrphanBlankNodesCleanupMiddleware(),
+    SystemCallWebIdMiddleware(),
+    CacherMiddleware(cacherConfig)
+  ],
+  logger: {
+    type: 'Console',
+    options: {
+      formatter: 'short',
+      level: 'info'
+    }
+  },
+  retryPolicy: {
+    enabled: true,
+    retries: 0,
+    delay: 100,
+    maxDelay: 30000,
+    factor: 2,
+    check: err => err && !!err.retryable
+  }
+};