test(examples): assert escaped text exactly

Make v0 and kanban DOM-aware escaped-text checks exact instead of substring-based while preserving the no-rendered-tag assertions.

req: html_safety/002

req: test/005

examples/kanban/src/main.rs

@@ -355,7 +355,8 @@ mod tests {
             .select(&selector("article.card[data-key=\"1\"]"))
             .next()
             .expect("card renders");
-        assert!(card.text().collect::<String>().contains("<b>Compile checked</b>"));
+        let title = card.select(&selector("strong")).next().expect("card title renders");
+        assert_eq!(title.text().collect::<String>(), "<b>Compile checked</b>");
         assert!(card.select(&selector("b")).next().is_none());
         assert_eq!(card.select(&selector("button[disabled]")).count(), 1);
     }