RDP session fixes: correct keyboard scancodes, clipboard sync, cursor shapes

Fix RDP keyboard input using FreeRDP's authoritative X11-keycode-to-scancode
table instead of ad hoc bit math, which misread punctuation keys as unrelated
letter keys (e.g. apostrophe as B) because X11 keycode numbering only
coincidentally overlaps PC/AT scancodes.

Add bidirectional clipboard sync (CF_UNICODETEXT) over the cliprdr channel,
and RDP pointer/cursor shape sync so the local cursor reflects what the
remote OS wants displayed (resize handles, text I-beam, etc.) instead of
staying a static arrow.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/rdp_display_widget.cpp

@@ -1,8 +1,10 @@
 #include "rdp_display_widget.h"
 
+#include <QCursor>
 #include <QKeyEvent>
 #include <QMouseEvent>
 #include <QPainter>
+#include <QPixmap>
 #include <QResizeEvent>
 #include <QTimer>
 #include <QWheelEvent>
@@ -16,7 +18,7 @@ QSize sanitizeSize(const QSize& size)
 }
 
 RdpDisplayWidget::RdpDisplayWidget(QWidget* parent)
-    : QWidget(parent), m_remoteSize(1280, 720)
+    : QWidget(parent), m_remoteSize(1280, 720), m_cursorMode(CursorMode::Default)
 {
     setFocusPolicy(Qt::StrongFocus);
     setMouseTracking(true);
@@ -61,6 +63,62 @@ void RdpDisplayWidget::clearFrame()
     update();
 }
 
+void RdpDisplayWidget::setCursorImage(const QImage& image, const QPoint& hotspot)
+{
+    m_cursorImage = image;
+    m_cursorHotspot = hotspot;
+    m_cursorMode = CursorMode::Custom;
+    applyCursor();
+}
+
+void RdpDisplayWidget::setCursorHidden()
+{
+    m_cursorMode = CursorMode::Hidden;
+    applyCursor();
+}
+
+void RdpDisplayWidget::setCursorDefault()
+{
+    m_cursorMode = CursorMode::Default;
+    applyCursor();
+}
+
+void RdpDisplayWidget::applyCursor()
+{
+    if (m_cursorMode == CursorMode::Hidden) {
+        setCursor(Qt::BlankCursor);
+        return;
+    }
+
+    if (m_cursorMode == CursorMode::Default || m_cursorImage.isNull()) {
+        unsetCursor();
+        return;
+    }
+
+    const QSize remote = effectiveRemoteSize();
+    const QRectF target = renderRect();
+    if (remote.isEmpty() || target.isEmpty()) {
+        setCursor(QCursor(QPixmap::fromImage(m_cursorImage),
+                          m_cursorHotspot.x(),
+                          m_cursorHotspot.y()));
+        return;
+    }
+
+    const qreal scale = target.width() / remote.width();
+    QImage scaledImage = m_cursorImage;
+    if (!qFuzzyCompare(scale, 1.0)) {
+        scaledImage = m_cursorImage.scaled(
+            qMax(1, qRound(m_cursorImage.width() * scale)),
+            qMax(1, qRound(m_cursorImage.height() * scale)),
+            Qt::IgnoreAspectRatio,
+            Qt::SmoothTransformation);
+    }
+
+    const int hotX = qBound(0, qRound(m_cursorHotspot.x() * scale), scaledImage.width());
+    const int hotY = qBound(0, qRound(m_cursorHotspot.y() * scale), scaledImage.height());
+    setCursor(QCursor(QPixmap::fromImage(scaledImage), hotX, hotY));
+}
+
 void RdpDisplayWidget::paintEvent(QPaintEvent* event)
 {
     Q_UNUSED(event);
@@ -84,6 +142,7 @@ void RdpDisplayWidget::resizeEvent(QResizeEvent* event)
     QWidget::resizeEvent(event);
     const QSize size = sanitizeSize(event->size());
     emit viewportSizeChanged(size.width(), size.height());
+    applyCursor();
 }
 
 void RdpDisplayWidget::keyPressEvent(QKeyEvent* event)