refactor(workspace): restore yaml exports and align docker builds

- return scenario export payloads as yaml to match existing workflows

- harden step reordering flow for drag-and-drop and one-based ui labels

- switch server container to workspace-lockfile installs and root ignore rules

.dockerignore

@@ -0,0 +1,9 @@
+.git
+.gitignore
+node_modules
+**/node_modules
+**/dist
+**/.DS_Store
+**/*.log
+data
+keys