feat(managed-secrets): add centrally managed secrets with GITOPS_ prefix pushed to multiple targets

Introduce managed secrets owned by GitOps that can be defined once and
pushed to any combination of projects/groups across connections. Values
are stored in OS keychain, secrets appear on targets as GITOPS_{key}.

ts_web/elements/index.ts

@@ -7,3 +7,4 @@ import './views/secrets/index.js';
 import './views/pipelines/index.js';
 import './views/buildlog/index.js';
 import './views/actions/index.js';
+import './views/managedsecrets/index.js';