fix(examples): keep test updates lower-aware

Move canonical example test helpers and docs off direct slot render shortcuts so even test-only slot updates use generated lower-aware HTML paths.

req: component/003

req: runtime/001

req: examples/003

examples/kanban/src/lib.rs

@@ -27,7 +27,7 @@ mod tests {
     #[test]
     fn kanban_board_updates_generated_slot() {
         fn render_board() -> impl IntoEffect {
-            board::slots::board.html(slhx::render(&empty_board()))
+            board::slots::board.html(super::ui::render(&empty_board()))
         }
 
         let effect = inspect(render_board());