test: introduce and set up unit tests in the UI (#486)

vitest.config.ts

@@ -0,0 +1,62 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { defineConfig } from "vitest/config";
+import vue from "@vitejs/plugin-vue";
+import vueJsx from "@vitejs/plugin-vue-jsx";
+import path from "path";
+import { createSvgIconsPlugin } from "vite-plugin-svg-icons";
+
+export default defineConfig({
+  plugins: [
+    vue(),
+    vueJsx(),
+    createSvgIconsPlugin({
+      iconDirs: [path.resolve(__dirname, "./src/assets/icons")],
+      symbolId: "[name]",
+    }),
+  ],
+  test: {
+    environment: "jsdom",
+    globals: true,
+    setupFiles: ["./src/test/setup.ts"],
+    deps: {
+      // vite-plugin-svg-icons uses non-standard exports and needs to be inlined
+      // to ensure correct module resolution during testing with Vitest.
+      inline: ["vite-plugin-svg-icons"],
+    },
+    coverage: {
+      provider: "v8",
+      reporter: ["text", "json", "html"],
+      exclude: [
+        "node_modules/",
+        "src/test/",
+        "**/*.d.ts",
+        "**/*.config.*",
+        "dist/",
+        "cypress/",
+        "src/types/",
+        "src/mock/",
+      ],
+    },
+  },
+  resolve: {
+    alias: {
+      "@": path.resolve(__dirname, "./src"),
+    },
+  },
+});