feat(FN-4206): add WorkflowResultsTab overflow regression coverage

Adds regression test coverage for WorkflowResultsTab overflow behavior, completing Step 3 of FN-4206.

Fusion-Task-Id: FN-4206

packages/dashboard/app/components/__tests__/WorkflowResultsTab.overflow.test.tsx

@@ -0,0 +1,48 @@
+import { describe, it, expect } from "vitest";
+import { render } from "@testing-library/react";
+import { loadAllAppCss } from "../../test/cssFixture";
+
+describe("WorkflowResultsTab overflow styles (FN-4206)", () => {
+  it("applies shrink/wrap rules for long workflow names", () => {
+    const style = document.createElement("style");
+    style.textContent = loadAllAppCss();
+    document.head.appendChild(style);
+
+    const longName = "verylongworkflowstepnamewithoutspaces".repeat(3);
+    const { container } = render(
+      <div>
+        <div className="workflow-result-header">
+          <div className="workflow-result-name">{longName}</div>
+        </div>
+        <div className="workflow-configured-header">
+          <div className="workflow-configured-title-row">
+            <div className="workflow-configured-name">{longName}</div>
+          </div>
+        </div>
+        <div className="workflow-output-modal-title">
+          <span className="workflow-output-modal-name">{longName}</span>
+        </div>
+      </div>,
+    );
+
+    const resultName = container.querySelector(".workflow-result-name");
+    const configuredName = container.querySelector(".workflow-configured-name");
+    const outputModalName = container.querySelector(".workflow-output-modal-name");
+    const configuredHeader = container.querySelector(".workflow-configured-header");
+
+    expect(resultName).toBeTruthy();
+    expect(configuredName).toBeTruthy();
+    expect(outputModalName).toBeTruthy();
+    expect(configuredHeader).toBeTruthy();
+
+    expect(getComputedStyle(resultName as Element).minWidth).toBe("0px");
+    expect(getComputedStyle(resultName as Element).wordBreak).toBe("break-word");
+    expect(getComputedStyle(configuredName as Element).minWidth).toBe("0px");
+    expect(getComputedStyle(configuredName as Element).wordBreak).toBe("break-word");
+    expect(getComputedStyle(outputModalName as Element).minWidth).toBe("0px");
+    expect(getComputedStyle(outputModalName as Element).wordBreak).toBe("break-word");
+    expect(getComputedStyle(configuredHeader as Element).flexWrap).toBe("wrap");
+
+    style.remove();
+  });
+});