[FIR] Report INAPPLICABLE_CANDIDATE or more specific diagnostic for callable references

... instead of just UNRESOLVED_REFERENCE when something went wrong
during resolution.

#KT-59401 related

compiler/testData/diagnostics/testsWithStdLib/coroutines/callableReference/suspendConversionForCallableReferences.fir.kt

@@ -10,7 +10,7 @@ suspend fun String.id(): String = this
 fun box() {
     val x = "f"
     builder {
-        go1(x::<!UNRESOLVED_REFERENCE!>id<!>)
-        go2(x::<!UNRESOLVED_REFERENCE!>id<!>)
+        go1(x::<!INAPPLICABLE_CANDIDATE!>id<!>)
+        go2(x::<!INAPPLICABLE_CANDIDATE!>id<!>)
     }
 }

compiler/testData/diagnostics/testsWithStdLib/coroutines/inference/callableReferenceToASuspendFunction.fir.kt

@@ -14,8 +14,8 @@ suspend fun bar(x: Int) {}
 
 fun test() {
     test0(::foo)
-    test1(::<!UNRESOLVED_REFERENCE!>foo<!>)
+    test1(::<!INAPPLICABLE_CANDIDATE!>foo<!>)
 
-    test0(::<!UNRESOLVED_REFERENCE!>bar<!>)
+    test0(::<!INAPPLICABLE_CANDIDATE!>bar<!>)
     test1(::bar)
 }