Split or glue together checks for not null and is instance + more intelligent use of filter vs filterTo

#KT-14284 Fixed
 #KT-14286 Fixed
 #KT-14287 Fixed
 #KT-14303 Fixed

idea/testData/intentions/loopToCallChain/smartCasts/smartCastRequired2.kt

@@ -1,6 +1,6 @@
 // WITH_RUNTIME
-// IS_APPLICABLE: false
-// IS_APPLICABLE_2: false
+// INTENTION_TEXT: "Replace with '...filter{}.map{}.firstOrNull()'"
+// INTENTION_TEXT_2: "Replace with 'asSequence()...filter{}.map{}.firstOrNull()'"
 fun foo(list: List<Any>, o: Any): Int? {
     <caret>for (s in list) {
         if (s is String && s.length > 0) {