Introduce "use expression body" inspection #KT-16063 Fixed

Converted from the relevant intention
Reported cases: one-liners, whens
Also, more exact caret detection in local inspection tests

idea/testData/quickfix/replaceWithSafeCall/noReplaceWithSafeCallForImplicitReceiver.kt

@@ -1,6 +1,5 @@
 // "Replace with safe (?.) call" "false"
 // ACTION: Add non-null asserted (!!) call
-// ACTION: Convert to expression body
 // ACTION: Replace with safe (this?.) call
 // ERROR: Only safe (?.) or non-null asserted (!!.) calls are allowed on a nullable receiver of type A?