Fix swap:animate test: add component stubs + serialize before contains?

The handler:ex-animate references ~examples/anim-result and ~docs/oob-code
which aren't loaded by the test runner. Added stub defcomps. Also fixed the
assertion: sx-swap returns a parsed tree (list), not a string, so contains?
was checking list membership instead of substring. Use str + string-contains?.

2522 passed, 0 failed.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/tests/test-swap-integration.sx

@@ -489,6 +489,11 @@
               (assert-true (contains? result "Success"))
               (assert-false (contains? result "Retrying")))))))))
 
+(defcomp
+  ~examples/anim-result
+  (&key color time)
+  (div :class color (p (str "Color: " color)) (p (str "Time: " time))))
+
 (defsuite
   "swap:animate"
   (deftest
@@ -498,10 +503,10 @@
       ((page "(div :id \"anim-result\")")
         (response (run-handler handler:ex-animate)))
       (let
-        ((result (sx-swap page "innerHTML" "anim-result" response)))
+        ((result (str (sx-swap page "innerHTML" "anim-result" response))))
         (do
-          (assert-true (contains? result "~anim-result"))
-          (assert-true (contains? result "12:00:00")))))))
+          (assert-true (string-contains? result "anim-result"))
+          (assert-true (string-contains? result "12:00:00")))))))
 
 (defsuite
   "swap:inline-edit"