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/UninitializedOrReassignedVariables.fir.kt

@@ -134,7 +134,7 @@ class AnonymousInitializers(var a: String, val b: String) {
     get() = 20
 
     init {
-        i = 13
+        <!VAL_REASSIGNMENT!>i<!> = 13
         <!VAL_REASSIGNMENT!>j<!> = 34
     }
 
@@ -174,7 +174,7 @@ class AnonymousInitializers(var a: String, val b: String) {
     val n: Int
 
     init {
-        while (n == 0) {
+        while (<!UNINITIALIZED_VARIABLE!>n<!> == 0) {
         }
         n = 10
         while (n == 0) {