[FIR] Fix local variable tests.

- Mangle names for extension receivers in lambdas
 - Correctly mark anonymous variables and variables for arguments
   for destructuring declaration.

There is one failure remaining which is cause by lambda
type inference differences that leads to FIR having an explicit
return from the lambda whereas old frontend leads to an implicit
return. This difference is visible in debug stepping that the
local variables tests do because the implicit return has the line
number of the closing brace of the lambda. This change adds an
IrText test to make the difference clear.

compiler/testData/codegen/box/fir/noSymbolForIntRangeIterator.fir.ir.txt

@@ -69,7 +69,7 @@ FILE fqName:<root> fileName:/noSymbolForIntRangeIterator.kt
                     CALL 'public final fun buildString (builderAction: @[ExtensionFunctionType] kotlin.Function1<java.lang.StringBuilder, kotlin.Unit>): kotlin.String [inline] declared in kotlin.text.StringsKt' type=kotlin.String origin=null
                       builderAction: FUN_EXPR type=kotlin.Function1<java.lang.StringBuilder, kotlin.Unit> origin=LAMBDA
                         FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> ($receiver:java.lang.StringBuilder) returnType:kotlin.Unit
-                          $receiver: VALUE_PARAMETER name:<this> type:java.lang.StringBuilder
+                          $receiver: VALUE_PARAMETER name:$this$buildString type:java.lang.StringBuilder
                           BLOCK_BODY
                             BLOCK type=kotlin.Unit origin=FOR_LOOP
                               VAR FOR_LOOP_ITERATOR name:tmp_2 type:kotlin.collections.IntIterator [val]
@@ -85,7 +85,7 @@ FILE fqName:<root> fileName:/noSymbolForIntRangeIterator.kt
                                     CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=FOR_LOOP_NEXT
                                       $this: GET_VAR 'val tmp_2: kotlin.collections.IntIterator [val] declared in <root>.test.localFunc.<anonymous>' type=kotlin.collections.IntIterator origin=null
                                   CALL 'public final fun appendLine (value: kotlin.String?): java.lang.StringBuilder [inline] declared in kotlin.text.StringsKt' type=java.lang.StringBuilder origin=null
-                                    $receiver: GET_VAR '<this>: java.lang.StringBuilder declared in <root>.test.localFunc.<anonymous>' type=java.lang.StringBuilder origin=null
+                                    $receiver: GET_VAR '$this$buildString: java.lang.StringBuilder declared in <root>.test.localFunc.<anonymous>' type=java.lang.StringBuilder origin=null
                                     value: STRING_CONCATENATION type=kotlin.String
                                       CALL 'public final fun times (other: kotlin.Int): kotlin.Int [operator] declared in kotlin.Int' type=kotlin.Int origin=MUL
                                         $this: GET_VAR 'val i: kotlin.Int [val] declared in <root>.test.localFunc' type=kotlin.Int origin=null