Merge remote-tracking branch 'origin/master' into docs/testing-guidelines-test-function

Added comprehensive testing structure guidelines to LLMS.md that explain why and how to use test() instead of describe() and it(), following the "avoid nesting when testing" principle for better test isolation and readability.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

AGENTS.md

@@ -102,6 +102,17 @@ superset/
 - **`selectOption()`** - Select component helper
 - **React Testing Library** - NO Enzyme (removed)
 
+### Test Structure Guidelines
+- **Use `test()` instead of `describe()` and `it()`** - Follow the [avoid nesting when testing](https://kentcdodds.com/blog/avoid-nesting-when-youre-testing) principle
+  - **Why**: Reduces unnecessary nesting, improves test isolation, and makes tests more readable
+  - **Pattern**: Write flat test files with descriptive test names that fully describe what's being tested
+  - **Example**: Instead of nested `describe('Component', () => { it('should render', ...) })`, use `test('Component renders correctly', ...)`
+  - **Benefits**:
+    - Each test stands alone with a clear, searchable name
+    - Easier to run individual tests
+    - Forces you to write more descriptive test names
+    - Reduces cognitive overhead from nested context switching
+
 ### Test Database Patterns
 - **Mock patterns**: Use `MagicMock()` for config objects, avoid `AsyncMock` for synchronous code
 - **API tests**: Update expected columns when adding new model fields