docs(agile): initialize docs

docs/architecture/testing-requirements.md

@@ -0,0 +1,7 @@
+# 8. Testing Requirements
+
+Testing is critical for ensuring the integrity of the system.
+*   **Unit Tests:** We will use **Vitest** for unit testing. Every composable and service function must have unit tests covering its logic.
+*   **Component Tests:** We will use **`@vue/test-utils`** to test individual Vue components. Tests should verify that components render correctly based on props and that they emit events when interacted with.
+*   **Test Location:** All test files will be located alongside the file they are testing, with a `.spec.ts` extension (e.g., `useLedger.spec.ts`).
+