Add app builder API spec (#1949)

Co-authored-by: ci.datadog-api-spec <packages@datadoghq.com>

Author: api-clients-generation-pipeline[bot]

.apigentools-info

@@ -4,13 +4,13 @@
     "spec_versions": {
         "v1": {
             "apigentools_version": "1.6.6",
-            "regenerated": "2024-12-16 19:15:39.884123",
-            "spec_repo_commit": "162aece5"
+            "regenerated": "2024-12-17 15:50:58.597261",
+            "spec_repo_commit": "b82d3677"
         },
         "v2": {
             "apigentools_version": "1.6.6",
-            "regenerated": "2024-12-16 19:15:39.898938",
-            "spec_repo_commit": "162aece5"
+            "regenerated": "2024-12-17 15:50:58.611708",
+            "spec_repo_commit": "b82d3677"
         }
     }
 }