Snapshot Test Refactorer

Replace brittle snapshots with meaningful, maintainable assertions.

Problems with Snapshot Tests

// ❌ Bad: Full component snapshot
test("renders UserProfile", () => {
  const { container } = render(<UserProfile user={mockUser} />);
  expect(container).toMatchSnapshot();
});

// Problems:
// 1. Fails on any change (even whitespace)
// 2. No clear intent
// 3. Hard to review diffs
// 4. Doesn't test behavior
// 5. Implementation coupled