Refactor: replace qAsConst with std::as_const across TetraIF; reduce compiler deprecation warnings

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

TetraIF/PrtCnv/LastTest/tetra_if.cpp

@@ -357,7 +357,7 @@ void TetraIF::onSendData()
   static char s_randomChar = 0;
   for (int i = 0; i < telegramsToSendNow; ++i)
   {
-    for (unsigned short dest_issi : qAsConst(m_issiList))
+    for (unsigned short dest_issi : std::as_const(m_issiList))
     {
       
       m_data[0] = s_randomChar++;
@@ -406,7 +406,7 @@ void TetraIF::parseISSIs(const QStringList &issiList)
 QString TetraIF::getIssisAsString() const
 {
   QString ret;
-  for (unsigned short issi : qAsConst(m_issiList))
+  for (unsigned short issi : std::as_const(m_issiList))
     ret += QString::number(issi) + QLatin1String(", ");
   return ret.left(ret.size() - 2);
 }