[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/imports/ImportOverloadFunctions.fir.kt

@@ -27,9 +27,9 @@ import k.two
 import k.all
 
 fun test() {
-    <!INAPPLICABLE_CANDIDATE!>zero<!>()
-    <!INAPPLICABLE_CANDIDATE!>zero<!>(1)
-    <!INAPPLICABLE_CANDIDATE!>zero<!>("")
+    <!NONE_APPLICABLE!>zero<!>()
+    <!NONE_APPLICABLE!>zero<!>(1)
+    <!NONE_APPLICABLE!>zero<!>("")
 
     one()
     <!INAPPLICABLE_CANDIDATE!>one<!>(1)
@@ -42,4 +42,4 @@ fun test() {
     all()
     all(1)
     all("")
-}
+}