refactor: replace jest with vitest

vitest.config.ts

@@ -0,0 +1,16 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    environment: "node",
+    include: ["src/**/*.{spec,test}.ts"],
+    coverage: {
+      enabled: true,
+      provider: "v8",
+      include: ["src/**/*.ts"],
+      exclude: ["src/**/*.{spec,test}.ts"],
+      reporter: ["lcov"],
+      reportsDirectory: "coverage",
+    },
+  },
+});