Cleanup, add tests and storybook

tests/unit/flowSteps.test.ts

@@ -0,0 +1,49 @@
+import { describe, it, expect } from "vitest";
+import {
+  FLOW_STEP_ORDER,
+  getNextStep,
+  getPreviousStep,
+  isValidStep,
+  getStepIndex,
+} from "../../app/create/utils/flowSteps";
+
+describe("flowSteps", () => {
+  it("places confirm-stakeholders immediately before final-review", () => {
+    const i = FLOW_STEP_ORDER.indexOf("confirm-stakeholders");
+    const j = FLOW_STEP_ORDER.indexOf("final-review");
+    expect(i).toBeGreaterThanOrEqual(0);
+    expect(j).toBe(i + 1);
+  });
+
+  it("getNextStep returns next step in order", () => {
+    expect(getNextStep("right-rail")).toBe("confirm-stakeholders");
+    expect(getNextStep("confirm-stakeholders")).toBe("final-review");
+  });
+
+  it("getNextStep returns null for last step or invalid", () => {
+    expect(getNextStep("completed")).toBeNull();
+    expect(getNextStep(null)).toBeNull();
+    // @ts-expect-error — exercise invalid step id at runtime
+    expect(getNextStep("not-a-step")).toBeNull();
+  });
+
+  it("getPreviousStep returns prior step or null", () => {
+    expect(getPreviousStep("final-review")).toBe("confirm-stakeholders");
+    expect(getPreviousStep("informational")).toBeNull();
+    expect(getPreviousStep(null)).toBeNull();
+  });
+
+  it("isValidStep reflects FLOW_STEP_ORDER membership", () => {
+    expect(isValidStep("select")).toBe(true);
+    expect(isValidStep("confirm-stakeholders")).toBe(true);
+    expect(isValidStep("nope")).toBe(false);
+    expect(isValidStep(null)).toBe(false);
+  });
+
+  it("getStepIndex matches position in FLOW_STEP_ORDER", () => {
+    expect(getStepIndex("informational")).toBe(0);
+    expect(getStepIndex("completed")).toBe(FLOW_STEP_ORDER.length - 1);
+    // @ts-expect-error — invalid step id
+    expect(getStepIndex("bogus")).toBe(-1);
+  });
+});