Add .prettierrc.json and refactor test files for improved formatting consistency:

- Introduced `.prettierrc.json` to enforce consistent code formatting across the project.
- Updated unit and e2e test files to address formatting issues, improve readability, and ensure alignment with the new Prettier configuration.

.prettierrc.json

@@ -0,0 +1,6 @@
+{
+  "endOfLine": "lf",
+  "tabWidth": 2,
+  "printWidth": 120,
+  "semi": true
+}