chore: configure vitest with project-based setup and coverage

vitest.config.ts

@@ -0,0 +1,13 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    projects: ["packages/*", "apps/*"],
+    coverage: {
+      provider: "v8",
+      reporter: ["text", "json", "html"],
+      exclude: ["node_modules/", "dist/"],
+    },
+    passWithNoTests: true,
+  },
+});