FIR: Support FirComparisonOperator in body transformers and DFA

^KT-31163 In Progress

compiler/testData/diagnostics/tests/regressions/DoubleDefine.fir.kt

@@ -11,7 +11,7 @@ fun takeFirst(expr: StringBuilder): Char {
 fun evaluateArg(expr: CharSequence, numbers: ArrayList<Int>): Int {
   if (expr.length == 0) throw Exception("Syntax error: Character expected");
   val c = <!INAPPLICABLE_CANDIDATE!>takeFirst<!>(expr)
-  if (c >= '0' && c <= '9') {
+  if (c <!UNRESOLVED_REFERENCE!>>=<!> '0' && c <!UNRESOLVED_REFERENCE!><=<!> '9') {
     val n = c <!UNRESOLVED_REFERENCE!>-<!> '0'
     if (!numbers.contains(n)) throw Exception("You used incorrect number: " + n)
     numbers.remove(n)

compiler/testData/diagnostics/tests/regressions/kt10843.fir.kt

@@ -3,6 +3,6 @@
 // See EA-76890 / KT-10843: NPE during analysis
 fun lambda(x : Int?) = x?.<!UNRESOLVED_REFERENCE!>let<!> <!UNRESOLVED_REFERENCE!>l<!> {
     y ->
-    if (y > 0) return@l x
+    if (y <!UNRESOLVED_REFERENCE!>><!> 0) return@l x
     y
 }!!