Adapts shared tests and common code to generated rtiddsgen API

Updates test suites and Lts/Common consumers to plain member access.

qt6-after/qt6-migrated-legatus/Lts/Common/CodeGen/StructBuilder.cpp

@@ -874,6 +874,13 @@ bool StructBuilder::fixupQVariantConversions(MemberInformation& mi) const
         datatype == QLatin1String("long long"))
     {
         mi.cpp.type = QStringLiteral("qint64");
+        // IDL `long long` is int64_t (long) in the rtiddsgen 4.7 output, while the Qt side is
+        // qint64 (long long). Those are distinct types, so assignments such as
+        // `optional<int64_t> = optional<qint64>` do not compile. Carry the generated type
+        // separately, as the sequence<octet> branch below already does, so the DDS-facing code
+        // emitted from cppDdsType() names the type the struct member really has. The spelling
+        // is the one rtiddsgen itself writes, matching what the `long` branch does with int32_t.
+        mi.cpp.ddsType = QStringLiteral("int64_t");
         mi.cpp.fromVariantPost = QStringLiteral(".toLongLong()");
         mi.cpp.fromJsonPost = QStringLiteral(".toDouble()");
         mi.cpp.toJsonPre = QStringLiteral("static_cast<qint64>(");
@@ -1039,7 +1046,7 @@ QVector<MemberInformation> StructBuilder::buildDbTableInformationFromIdlData(con
                 pre += columnNamePrefix;
             pre += member.name + QLatin1Char('_');
             ret += buildDbTableInformationFromIdlData(cttiChild, tableName, StructBuilder::camelCaseToUnderline(pre),
-                                                      cppStructure + member.name + QStringLiteral("()."));
+                                                      cppStructure + member.name + QStringLiteral("."));
             continue;
         }