fix(examples): use lower-aware slot html updates

Move canonical examples and docs off direct RenderSlotExt render shortcuts so slot updates use generated render/lowering before HTML replacement, preserving runtime metadata for follow-up interactions.

req: component/003

req: runtime/001

req: dx/006

req: examples/003

examples/kanban/src/lib.rs

@@ -6,7 +6,7 @@ mod tests {
     use super::ui::{board, board_card};
     use hemplate::Hemplate;
     use scraper::{Html, Selector};
-    use slhx::{Effect, IntoEffect, Payload, RenderSlotExt};
+    use slhx::{Effect, IntoEffect, Payload};
     use slhx_test::inspect;
 
     #[derive(Hemplate)]
@@ -27,7 +27,7 @@ mod tests {
     #[test]
     fn kanban_board_updates_generated_slot() {
         fn render_board() -> impl IntoEffect {
-            board::slots::board.render(&empty_board())
+            board::slots::board.html(slhx::render(&empty_board()))
         }
 
         let effect = inspect(render_board());