feat: add operational timeline workspace

src/features/workbench/workspace/workspace-context.test.ts

@@ -0,0 +1,46 @@
+import { describe, expect, it } from "vitest";
+import { createAnalysisArtifactFixture } from "./analysis-document-fixtures";
+import { createInitialWorkspaceContext, reduceWorkspaceContext } from "./workspace-context";
+
+describe("workspace context", () => {
+  it("keeps operational time independent from artifact analytical time", () => {
+    const artifact = createAnalysisArtifactFixture(0, 0);
+    const withArtifact = reduceWorkspaceContext(createInitialWorkspaceContext(), {
+      type: "sync-artifact",
+      artifact
+    });
+    const selectedEvent = reduceWorkspaceContext(withArtifact, {
+      type: "select-operational-event",
+      eventId: "event-1",
+      cursorTime: "2026-08-19T10:30:00.000Z"
+    });
+
+    expect(selectedEvent.analytical.timeRange).toEqual(artifact.analyticalTimeRange);
+    expect(selectedEvent.operational.cursorTime).toBe("2026-08-19T10:30:00.000Z");
+  });
+
+  it("updates analytical context without moving the operational cursor", () => {
+    const initial = createInitialWorkspaceContext(new Date("2026-08-19T08:00:00.000Z"));
+    const cursorTime = initial.operational.cursorTime;
+    const withArtifact = reduceWorkspaceContext(initial, {
+      type: "sync-artifact",
+      artifact: createAnalysisArtifactFixture(1, 1)
+    });
+
+    expect(withArtifact.operational.cursorTime).toBe(cursorTime);
+    expect(withArtifact.analytical.artifactId).toBeTruthy();
+  });
+
+  it("clears selection while retaining cursor until returning to now", () => {
+    const initial = createInitialWorkspaceContext();
+    const selected = reduceWorkspaceContext(initial, {
+      type: "select-operational-event",
+      eventId: "event-2",
+      cursorTime: "2026-08-19T13:10:00.000Z"
+    });
+    const cleared = reduceWorkspaceContext(selected, { type: "clear-operational-event" });
+
+    expect(cleared.operational.selectedEventId).toBeNull();
+    expect(cleared.operational.cursorTime).toBe("2026-08-19T13:10:00.000Z");
+  });
+});