Write end offsets to _debug even if validation fails

Fixes a regression introduced in
7154301 that was well noticeable in the
devel Web IDE with the
kaitai-io/kaitai_struct_webide#156 feature: a
field with a failed validation (specified by the `contents` or `valid`
key) no longer had its byte range highlighted in the hex dump. This is
because the aforementioned commit changed the order of operations in the
generated JavaScript code (in debug mode, or more precisely with
`--read-pos`) so that the assignment of the end offset to the `_debug`
map for a field with `contents` or `valid` was done *after* the `if`
statement performing the validation, which meant that the end offset was
not assigned if the validation failed.

A nice side effect of this commit is that it eliminates duplicate
`this._debug.{ATTR_NAME}.arr[i]` assignments in the case of a field with
type switching and `repeat`, such as when you compile
https://github.com/kaitai-io/kaitai_struct_tests/blob/9f782819b70db6069674995b969d2b801c86a515/formats/switch_repeat_expr.ksy
in `--read-pos` mode (in JavaScript, it removes the
`this._debug.body.arr[i] = ...` assignments from every branch of the
`switch` statement, which are indeed unnecessary, because the exact same
assignments already exist around the `switch` statement as well).

Note: this commit unfortunately doesn't have any impact on the current
set of test formats in
[`formats/`](https://github.com/kaitai-io/kaitai_struct_tests/tree/9f782819b70db6069674995b969d2b801c86a515/formats)
when compiled with the usual settings in
[`build-formats`](https://github.com/kaitai-io/kaitai_struct_tests/blob/9f782819b70db6069674995b969d2b801c86a515/build-formats).
This is because we only test the debug mode on 4 formats that have the
`meta/ks-debug: true` key, and none of them has a field with `contents`
or `valid`. But if you add `--debug` to the KSC incantation in
`build-formats`, you will see the changes.

shared/src/main/scala/io/kaitai/struct/languages/components/CommonReads.scala

@@ -25,12 +25,11 @@ trait CommonReads extends LanguageCompiler {
         normalIO
     }
 
-    val needsDebug = attrDebugNeeded(id)
+    val needsArrayDebug = attrDebugNeeded(id) && attr.cond.repeat != NoRepeat
 
-    if (needsDebug) {
+    if (needsArrayDebug) {
       attrDebugStart(id, attr.dataType, Some(io), NoRepeat)
-      if (attr.cond.repeat != NoRepeat)
-        attrDebugArrInit(id, attr.dataType)
+      attrDebugArrInit(id, attr.dataType)
     }
 
     defEndian match {
@@ -45,7 +44,7 @@ trait CommonReads extends LanguageCompiler {
         attrParse0(id, attr, io, Some(fe))
     }
 
-    if (needsDebug)
+    if (needsArrayDebug)
       attrDebugEnd(id, attr.dataType, io, NoRepeat)
 
     // More position management + set calculated flag after parsing for ParseInstanceSpecs
@@ -75,7 +74,16 @@ trait CommonReads extends LanguageCompiler {
         condRepeatUntilHeader(id, io, attr.dataType, untilExpr)
       case NoRepeat =>
     }
+
+    val needsDebug = attrDebugNeeded(id)
+    if (needsDebug)
+      attrDebugStart(id, attr.dataType, Some(io), attr.cond.repeat)
+
     attrParse2(id, attr.dataType, io, attr.cond.repeat, false, defEndian)
+
+    if (needsDebug)
+      attrDebugEnd(id, attr.dataType, io, attr.cond.repeat)
+
     attrValidateAll(attr)
     attr.cond.repeat match {
       case RepeatEos =>
@@ -94,7 +102,15 @@ trait CommonReads extends LanguageCompiler {
   def attrDebugArrInit(attrId: Identifier, attrType: DataType): Unit = {}
   def attrDebugEnd(attrName: Identifier, attrType: DataType, io: String, repeat: RepeatSpec): Unit = {}
 
-  def attrDebugNeeded(attrId: Identifier): Boolean = false
+  def attrDebugNeeded(attrId: Identifier): Boolean = {
+    if (!config.readStoresPos)
+      return false
+
+    attrId match {
+      case _: NamedIdentifier | _: NumberedIdentifier | _: InstanceIdentifier => true
+      case _ => false
+    }
+  }
 
   /**
     * Runs all validation procedures requested for an attribute.

shared/src/main/scala/io/kaitai/struct/languages/components/EveryReadIsExpression.scala

@@ -31,10 +31,6 @@ trait EveryReadIsExpression
     assignTypeOpt: Option[DataType] = None
   ): Unit = {
     val assignType = assignTypeOpt.getOrElse(dataType)
-    val needsDebug = attrDebugNeeded(id) && rep != NoRepeat
-
-    if (needsDebug)
-      attrDebugStart(id, dataType, Some(io), rep)
 
     dataType match {
       case t: UserType =>
@@ -61,9 +57,6 @@ trait EveryReadIsExpression
         val expr = parseExpr(dataType, assignType, io, defEndian)
         handleAssignment(id, expr, rep, isRaw)
     }
-
-    if (needsDebug)
-      attrDebugEnd(id, dataType, io, rep)
   }
 
   def attrBytesTypeParse(
@@ -255,14 +248,4 @@ trait EveryReadIsExpression
       attrDebugStart(instName, dataType, None, NoRepeat)
     handleAssignmentSimple(instName, expression(value))
   }
-
-  override def attrDebugNeeded(attrId: Identifier): Boolean = {
-    if (!config.readStoresPos)
-      return false
-
-    attrId match {
-      case _: NamedIdentifier | _: NumberedIdentifier | _: InstanceIdentifier => true
-      case _ => super.attrDebugNeeded(attrId)
-    }
-  }
 }