feat: add ui.seamColor accent

src/config/ui-seam-color.test.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+
+import { validateConfigObject } from "./config.js";
+
+describe("ui.seamColor", () => {
+  it("accepts hex colors", () => {
+    const res = validateConfigObject({ ui: { seamColor: "#FF4500" } });
+    expect(res.ok).toBe(true);
+  });
+
+  it("rejects non-hex colors", () => {
+    const res = validateConfigObject({ ui: { seamColor: "lobster" } });
+    expect(res.ok).toBe(false);
+  });
+
+  it("rejects invalid hex length", () => {
+    const res = validateConfigObject({ ui: { seamColor: "#FF4500FF" } });
+    expect(res.ok).toBe(false);
+  });
+});