CFA: detect captured writes more precisely

So #KT-14381 Fixed
So #KT-13597 Fixed
Also refactors captured writes detection inside DFA

compiler/testData/diagnostics/tests/smartCasts/varInInitNoPrimary.kt

@@ -0,0 +1,22 @@
+class Your {
+    init {
+        var y: String? = "xyz"
+        if (y != null) {
+            // Bug that should be fixed
+            // Problem: descriptorToDeclaration cannot get here init block by its descriptor
+            // See PreliminaryDeclarationVisitor.getVisitorByVariable
+            <!SMARTCAST_IMPOSSIBLE!>y<!>.hashCode()
+        }
+    }
+
+    constructor()
+}
+
+class Normal {
+    init {
+        var y: String? = "xyz"
+        if (y != null) {
+            <!DEBUG_INFO_SMARTCAST!>y<!>.hashCode()
+        }
+    }
+}