Copilot review instructions enhancement (#5115)

* Copilot review instructions enhancement

* CR fixes

* CR fixes

.github/instructions/unit-tests.instructions.md

@@ -0,0 +1,24 @@
+---
+applyTo: "**/*.spec.ts"
+---
+
+# Unit testing best practices
+
+* Write unit tests for components, services, and pipes using Jasmine and Karma.
+* Test cases should be reasonably grouped based on tested functionality/behaviour using describe blocks.
+* Use plain English test names based on the should <expectedBehavior> when <stateUnderTest> pattern as a guideline.
+* Use Angular's TestBed for component testing with mocked dependencies
+* Avoid Direct Calls to Component Lifecycle Hooks: Instead of directly invoking lifecycle hooks like `ngOnInit()`, use Angular's testing utilities to trigger them naturally. For example, use `fixture.detectChanges()` to trigger change detection, which will automatically call `ngOnInit()` and other lifecycle hooks in the correct order.
+* Use fixture.componentRef.setInput() Instead of Direct Input Assignment: When testing components with inputs, use `fixture.componentRef.setInput()` to set input values. This method ensures that Angular's change detection is properly triggered, allowing the component to react to input changes as it would in a real application.
+* Use `provideMockStore` for testing components that rely on NgRx state management. This allows you to mock the store and control the state during tests without needing to set up a full NgRx environment.
+* Mock HTTP requests using `provideHttpClientTesting()`
+* Import only the minimal required modules
+* Avoid NO_ERRORS_SCHEMA and CUSTOM_ELEMENTS_SCHEMA in tests to ensure proper error detection
+* Do not verify mocked methods
+* Avoid mocking component methods unless necessary; prefer testing actual behavior
+* Avoid testing private methods directly; test them through public methods instead
+* Avoid testing methods or behaviours of children components; use shallow testing or mock child components instead
+* Use the overrideProviders API to replace components, directives, pipes, or services declared deep within the module hierarchy
+* Avoid async/await in synchronous unit tests
+* Prefer data-automation-id over CSS class when possible
+* Do not use toBeDefined() to check if an element is visible.