[FIR] Refactor effective visibility calculation

Before this commit, we had effective visibility as a part of FIR status,
so it was integrated into the full pipeline. In this commit,
we introduced "effective visibility as a service" which is now used
only by exposed visibility checker. This allows us to make the thing
universal for all FIR nodes, including nodes for Java / deserialized.

compiler/fir/analysis-tests/testData/loadCompiledKotlin/classObject/ClassObjectDefaultVisibility.txt

@@ -72,3 +72,4 @@ public final class Pub : R|kotlin/Any| {
     }
 
 }
+

compiler/fir/analysis-tests/testData/loadCompiledKotlin/classObject/ClassObjectExplicitVisibility.txt

@@ -87,3 +87,4 @@ public final class PubPub : R|kotlin/Any| {
     }
 
 }
+