Doc: Add missing property docs

Pick-to: 6.10 6.8
Task-number: QTBUG-140629
Change-Id: If91c00f72a52bfd0b62790d44cd5e489281a767d
Reviewed-by: Dennis Oberst <dennis.oberst@qt.io>
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

src/grpc/qgrpcclientbase.cpp

@@ -44,6 +44,16 @@ QT_BEGIN_NAMESPACE
     Indicates that a new channel got attached to the client.
 */
 
+/*!
+    \property QGrpcClientBase::channel
+    \since 6.7
+
+    This property holds the channel attached to this client. The channel is used
+    as the transport layer for gRPC operations.
+
+    \sa attachChannel()
+*/
+
 namespace {
 template <typename Operation>
 inline constexpr bool IsStream = false;

src/grpcquick/qqmlgrpccalloptions.cpp

@@ -35,6 +35,15 @@ QQmlGrpcCallOptions::QQmlGrpcCallOptions(QObject *parent)
 
 QQmlGrpcCallOptions::~QQmlGrpcCallOptions() = default;
 
+/*!
+    \property QtGrpcQuickPrivate::QQmlGrpcCallOptions::deadlineTimeout
+
+    This property holds the deadline timeout for the gRPC call in milliseconds.
+    The deadline specifies how long the client is willing to wait for a reply
+    from the server. If the deadline is exceeded, the call will be canceled.
+
+    The default value is \c 0, which means no deadline is set.
+*/
 qint64 QQmlGrpcCallOptions::deadlineTimeout() const
 {
     Q_D(const QQmlGrpcCallOptions);
@@ -56,6 +65,13 @@ const QGrpcCallOptions &QQmlGrpcCallOptions::options() const & noexcept
     return d->options;
 }
 
+/*!
+    \property QtGrpcQuickPrivate::QQmlGrpcCallOptions::metadata
+
+    This property holds the metadata to be sent with the gRPC call. Metadata
+    consists of key-value pairs that are sent as HTTP/2 headers in the gRPC
+    request.
+*/
 QQmlGrpcMetadata *QQmlGrpcCallOptions::metadata() const
 {
     Q_D(const QQmlGrpcCallOptions);