[FIR] Improve diagnostic reporting & don't use error symbol for candidate if possible

Also introduce few new diagnostics:
- NONE_APPLICABLE more many inapplicable candidates
- HIDDEN for visible candidates

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

@@ -11,8 +11,8 @@ 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 <!UNRESOLVED_REFERENCE!>>=<!> '0' && c <!UNRESOLVED_REFERENCE!><=<!> '9') {
-    val n = c <!UNRESOLVED_REFERENCE!>-<!> '0'
+  if (c >= '0' && c <= '9') {
+    val n = c - '0'
     if (!numbers.contains(n)) throw Exception("You used incorrect number: " + n)
     numbers.remove(n)
     return n

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

@@ -5,5 +5,5 @@ fun <T : Bar, T1> foo(x : Int) {}
 fun <T1, T : Foo> foo(x : Long) {}
 
 fun f(): Unit {
-    <!INAPPLICABLE_CANDIDATE!>foo<!><Int, Int>(1)
+    <!NONE_APPLICABLE!>foo<!><Int, Int>(1)
 }

compiler/testData/diagnostics/tests/regressions/kt10633.fir.kt

@@ -13,7 +13,7 @@ operator fun Int.set(s: Int, x: String = "", z: Int) {
 fun main() {
     <!INAPPLICABLE_CANDIDATE!>1[2] = 1<!>
     1.set(2, z = 1)
-    <!UNRESOLVED_REFERENCE!>1[2] += 1<!>
+    1[2] += 1
 
     1.<!INAPPLICABLE_CANDIDATE!>set<!>(2, 1)
 }

compiler/testData/diagnostics/tests/regressions/kt282.fir.kt

@@ -12,7 +12,7 @@ operator fun Int?.contains(x : Int) : Boolean = false
 fun f(): Unit {
     var set : Set? = null
     val i : Int? = null
-    i <!INAPPLICABLE_CANDIDATE!>+<!> 1
+    i <!NONE_APPLICABLE!>+<!> 1
     set + 1
     1 <!INAPPLICABLE_CANDIDATE!>in<!> set
     1 in 2