Add app builder API spec (#415)

Co-authored-by: ci.datadog-api-spec <packages@datadoghq.com>
Co-authored-by: Kevin Zou <kevin.zou@datadoghq.com>
Co-authored-by: api-clients-generation-pipeline[bot] <54105614+api-clients-generation-pipeline[bot]@users.noreply.github.com>

.apigentools-info

@@ -4,13 +4,13 @@
     "spec_versions": {
         "v1": {
             "apigentools_version": "1.6.6",
-            "regenerated": "2024-12-16 19:15:41.785620",
-            "spec_repo_commit": "162aece5"
+            "regenerated": "2024-12-17 15:51:05.376779",
+            "spec_repo_commit": "b82d3677"
         },
         "v2": {
             "apigentools_version": "1.6.6",
-            "regenerated": "2024-12-16 19:15:41.800183",
-            "spec_repo_commit": "162aece5"
+            "regenerated": "2024-12-17 15:51:05.390982",
+            "spec_repo_commit": "b82d3677"
         }
     }
 }