test(portal-openbaar): drive the openbaar register page — list, search, empty state (refs #10)

Scaffolds the anonymous openbaar Angular app (mirrors self-service: standalone +
signals, NL DS via the ui lib, no auth) and adds a failing register-page spec:
loads the public register from the BFF on open, searches by term, and shows an
empty-state message. The stub page renders only the heading, so the list/search/
empty-state assertions fail (red).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/openbaar/project.json

@@ -0,0 +1,80 @@
+{
+  "name": "openbaar",
+  "$schema": "../../node_modules/nx/schemas/project-schema.json",
+  "projectType": "application",
+  "prefix": "app",
+  "sourceRoot": "apps/openbaar/src",
+  "tags": [],
+  "targets": {
+    "build": {
+      "executor": "@angular/build:application",
+      "outputs": ["{options.outputPath}"],
+      "defaultConfiguration": "production",
+      "options": {
+        "outputPath": "dist/apps/openbaar",
+        "browser": "apps/openbaar/src/main.ts",
+        "tsConfig": "apps/openbaar/tsconfig.app.json",
+        "assets": [
+          {
+            "glob": "**/*",
+            "input": "apps/openbaar/public"
+          }
+        ],
+        "styles": ["apps/openbaar/src/styles.css"]
+      },
+      "configurations": {
+        "production": {
+          "budgets": [
+            {
+              "type": "initial",
+              "maximumWarning": "1mb",
+              "maximumError": "2mb"
+            },
+            {
+              "type": "anyComponentStyle",
+              "maximumWarning": "4kb",
+              "maximumError": "8kb"
+            }
+          ],
+          "outputHashing": "all"
+        },
+        "development": {
+          "optimization": false,
+          "extractLicenses": false,
+          "sourceMap": true
+        }
+      }
+    },
+    "serve": {
+      "continuous": true,
+      "executor": "@angular/build:dev-server",
+      "defaultConfiguration": "development",
+      "configurations": {
+        "production": {
+          "buildTarget": "openbaar:build:production"
+        },
+        "development": {
+          "buildTarget": "openbaar:build:development"
+        }
+      }
+    },
+    "lint": {
+      "executor": "@nx/eslint:lint"
+    },
+    "test": {
+      "executor": "@angular/build:unit-test",
+      "options": {
+        "watch": false
+      }
+    },
+    "serve-static": {
+      "continuous": true,
+      "executor": "@nx/web:file-server",
+      "options": {
+        "buildTarget": "openbaar:build",
+        "staticFilePath": "dist/apps/openbaar/browser",
+        "spa": true
+      }
+    }
+  }
+}