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

server/test/scenario-step-output.spec.ts

@@ -50,12 +50,11 @@ describe("ScenarioRunStepEntity.output + helpers.getStepOutput", () => {
   /** Create a step and return its id. */
   async function createStep(
     scenarioId: string,
-    order: number,
+    _order: number,
     execCode: string,
     sessionName = "output-test-session",
   ): Promise<string> {
     const step = await scenarioService.createStep(scenarioId, {
-      order,
       sessionName,
       execCode,
     });