FIR: check assignments and references to members in constructors

I.e. emit VAL_REASSIGNMENT on repeated assignments to `this.something`,
UNINITIALIZED_VARIABLE on reads of it before any assignment if there is
no initializer, and CAPTURED_MEMBER_VAL_INITIALIZATION on assignments
inside non-called-in-place functions and named classes.

^KT-55528 Fixed

compiler/testData/diagnostics/tests/controlFlowAnalysis/assignmentInLocalsInConstructor.fir.kt

@@ -7,7 +7,7 @@ class Test {
         val t = object {
             fun some() {
                 // See KT-13597
-                a = "12"
+                <!VAL_REASSIGNMENT!>a<!> = "12"
             }
         }
 
@@ -20,7 +20,7 @@ class Test2 {
     init {
         val t = object {
             fun some() {
-                a = "12"
+                <!VAL_REASSIGNMENT!>a<!> = "12"
             }
         }
 
@@ -41,7 +41,7 @@ class Test4 {
     init {
         exec {
             // See KT-14381
-            a = "12"
+            <!CAPTURED_MEMBER_VAL_INITIALIZATION!>a<!> = "12"
         }
         a = "34"
     }