test: raise frontend coverage baselines

adminfront/src/components/ui/avatar.test.tsx

@@ -0,0 +1,49 @@
+import React from "react";
+import { act } from "react";
+import { createRoot } from "react-dom/client";
+import { afterEach, describe, expect, it } from "vitest";
+import { Avatar, AvatarFallback, AvatarImage } from "./avatar";
+
+let container: HTMLDivElement | null = null;
+
+const render = async (element: React.ReactElement) => {
+  container = document.createElement("div");
+  document.body.appendChild(container);
+  const root = createRoot(container);
+  await act(async () => {
+    root.render(element);
+  });
+  return root;
+};
+
+afterEach(() => {
+  if (container) {
+    container.remove();
+    container = null;
+  }
+});
+
+describe("Avatar", () => {
+  it("renders image and fallback with merged classes", async () => {
+    const root = await render(
+      <Avatar className="custom-root" data-testid="avatar">
+        <AvatarImage
+          alt="Admin user"
+          className="custom-image"
+          src="/avatar.png"
+        />
+        <AvatarFallback className="custom-fallback">AU</AvatarFallback>
+      </Avatar>,
+    );
+
+    const avatar = container?.querySelector("[data-testid='avatar']");
+    const fallback = container?.textContent;
+
+    expect(avatar?.className).toContain("custom-root");
+    expect(fallback).toContain("AU");
+
+    await act(async () => {
+      root.unmount();
+    });
+  });
+});