docs: Fix: gdk->gtk and gdk->gsk links

gi-docgen can only generate links for dependencies, so we have
to manually expand to a relative url here.

fixup

gdk/gdkclipboard.c

@@ -529,8 +529,9 @@ gdk_clipboard_get_content (GdkClipboard *clipboard)
  * exit. Depending on the platform, the functionality may not be available
  * unless a "clipboard manager" is running.
  *
- * This function is called automatically when a [class@Gtk.Application] is
- * shut down, so you likely don't need to call it.
+ * This function is called automatically when a
+ * [GtkApplication](../gtk4/class.Application.html)
+ * is shut down, so you likely don't need to call it.
  */
 void
 gdk_clipboard_store_async (GdkClipboard        *clipboard,

gdk/gdkcursor.c

@@ -47,7 +47,8 @@
  * Cursors by themselves are not very interesting: they must be bound to a
  * window for users to see them. This is done with [method@Gdk.Surface.set_cursor]
  * or [method@Gdk.Surface.set_device_cursor]. Applications will typically
- * use higher-level GTK functions such as [method@Gtk.Widget.set_cursor] instead.
+ * use higher-level GTK functions such as [gtk_widget_set_cursor()](../gtk4/method.Widget.set_cursor.html)
+ * instead.
  *
  * Cursors are not bound to a given [class@Gdk.Display], so they can be shared.
  * However, the appearance of cursors may vary when used on different

gdk/gdkdisplay.c

@@ -1189,9 +1189,9 @@ _gdk_display_get_next_serial (GdkDisplay *display)
  * Indicates to the GUI environment that the application has
  * finished loading, using a given identifier.
  *
- * GTK will call this function automatically for [class@Gtk.Window]
+ * GTK will call this function automatically for [GtkWindow](../gtk4/class.Window.html)
  * with custom startup-notification identifier unless
- * [method@Gtk.Window.set_auto_startup_notification]
+ * [gtk_window_set_auto_startup_notification()](../gtk4/method.Window.set_auto_startup_notification.html)
  * is called to disable that feature.
  *
  * Deprecated: 4.10: Using [method@Gdk.Toplevel.set_startup_id] is sufficient

gdk/gdkdrawcontext.c

@@ -305,8 +305,8 @@ gdk_draw_context_get_surface (GdkDrawContext *context)
  *
  * When using GTK, the widget system automatically places calls to
  * gdk_draw_context_begin_frame() and gdk_draw_context_end_frame() via the
- * use of [class@Gsk.Renderer]s, so application code does not need to call
- * these functions explicitly.
+ * use of [GskRenderer](../gsk4/class.Renderer.html)s, so application code
+ * does not need to call these functions explicitly.
  */
 void
 gdk_draw_context_begin_frame (GdkDrawContext       *context,

gdk/gdkframeclock.c

@@ -166,7 +166,8 @@ gdk_frame_clock_class_init (GdkFrameClockClass *klass)
    *
    * Animations should be updated using [method@Gdk.FrameClock.get_frame_time].
    * Applications can connect directly to this signal, or use
-   * [method@Gtk.Widget.add_tick_callback] as a more convenient interface.
+   * [gtk_widget_add_tick_callback()](../gtk4/method.Widget.add_tick_callback.html)
+   * as a more convenient interface.
    */
   signals[UPDATE] =
     g_signal_new (g_intern_static_string ("update"),
@@ -203,7 +204,8 @@ gdk_frame_clock_class_init (GdkFrameClockClass *klass)
    *
    * The frame is repainted. GDK normally handles this internally and
    * emits [signal@Gdk.Surface::render] signals which are turned into
-   * [signal@Gtk.Widget::snapshot] signals by GTK.
+   * [GtkWidget::snapshot](../gtk4/signal.Widget.snapshot.html) signals
+   * by GTK.
    */
   signals[PAINT] =
     g_signal_new (g_intern_static_string ("paint"),

gdk/gdkpaintable.c

@@ -681,7 +681,8 @@ gdk_empty_paintable_init (GdkEmptyPaintable *self)
  * This is often useful for implementing the
  * [vfunc@Gdk.Paintable.get_current_image] virtual function
  * when the paintable is in an incomplete state (like a
- * [class@Gtk.MediaStream] before receiving the first frame).
+ * [GtkMediaStream](../gtk4/class.MediaStream.html) before receiving
+ * the first frame).
  *
  * Returns: (transfer full): a `GdkPaintable`
  */

gdk/gdkpopuplayout.c

@@ -56,9 +56,9 @@
  * [method@Gdk.Popup.get_position_x], [method@Gdk.Popup.get_position_y],
  * [method@Gdk.Popup.get_rect_anchor] and [method@Gdk.Popup.get_surface_anchor]
  * after the popup has been presented. This can be used to adjust the rendering.
- * For example, [class@Gtk.Popover] changes its arrow position accordingly.
- * But you have to be careful avoid changing the size of the popover, or it
- * has to be presented again.
+ * For example, [GtkPopover](../gtk4/class.Popover.html) changes its arrow position
+ * accordingly. But you have to be careful avoid changing the size of the popover,
+ * or it has to be presented again.
  */
 
 struct _GdkPopupLayout

gdk/gdksnapshot.c

@@ -26,7 +26,7 @@
  *
  * Base type for snapshot operations.
  *
- * The subclass of `GdkSnapshot` used by GTK is [class@Gtk.Snapshot].
+ * The subclass of `GdkSnapshot` used by GTK is [GtkSnapshot](../gtk4/class.Snapshot.html).
  */
 
 G_DEFINE_ABSTRACT_TYPE (GdkSnapshot, gdk_snapshot, G_TYPE_OBJECT)

gdk/gdksurface.c

@@ -57,7 +57,7 @@
  * A `GdkSurface` is a rectangular region on the screen.
  *
  * It’s a low-level object, used to implement high-level objects
- * such as [class@Gtk.Window] or [class@Gtk.Dialog] in GTK.
+ * such as [GtkWindow](../gtk4/class.Window.html).
  *
  * The surfaces you see in practice are either [iface@Gdk.Toplevel] or
  * [iface@Gdk.Popup], and those interfaces provide much of the required
@@ -1716,7 +1716,7 @@ gdk_surface_get_device_position (GdkSurface       *surface,
  * For toplevel surfaces, withdraws them, so they will no longer be
  * known to the window manager; for all surfaces, unmaps them, so
  * they won’t be displayed. Normally done automatically as
- * part of [method@Gtk.Widget.hide].
+ * part of [gtk_widget_hide()](../gtk4/method.Widget.hide.html).
  */
 void
 gdk_surface_hide (GdkSurface *surface)
@@ -2636,7 +2636,7 @@ gdk_surface_get_scale (GdkSurface *surface)
  * GTK will update this property automatically if the @surface background
  * is opaque, as we know where the opaque regions are. If your surface
  * background is not opaque, please update this property in your
- * [vfunc@Gtk.Widget.css_changed] handler.
+ * [GtkWidgetClass.css_changed](../gtk4/vfunc.Widget.css_changed.html) handler.
  */
 void
 gdk_surface_set_opaque_region (GdkSurface      *surface,

gdk/gdktoplevel.c

@@ -377,8 +377,9 @@ gdk_toplevel_lower (GdkToplevel *toplevel)
  *
  * Sets keyboard focus to @surface.
  *
- * In most cases, [method@Gtk.Window.present_with_time] should be
- * used on a [class@Gtk.Window], rather than calling this function.
+ * In most cases, [gtk_window_present_with_time()](../gtk4/method.Window.present_with_time.html)
+ * should be used on a [GtkWindow](../gtk4/class.Window.html), rather than
+ * calling this function.
  */
 void
 gdk_toplevel_focus (GdkToplevel *toplevel,
@@ -437,8 +438,8 @@ gdk_toplevel_set_title (GdkToplevel *toplevel,
  * Sets the startup notification ID.
  *
  * When using GTK, typically you should use
- * [method@Gtk.Window.set_startup_id] instead of this
- * low-level function.
+ * [gtk_window_set_startup_id()](../gtk4/method.Window.set_startup_id.html)
+ * instead of this low-level function.
  */
 void
 gdk_toplevel_set_startup_id (GdkToplevel *toplevel,
@@ -461,8 +462,8 @@ gdk_toplevel_set_startup_id (GdkToplevel *toplevel,
  * allows the window manager to do things like center @surface
  * on @parent and keep @surface above @parent.
  *
- * See [method@Gtk.Window.set_transient_for] if you’re using
- * [class@Gtk.Window] or [class@Gtk.Dialog].
+ * See [gtk_window_set_transient_for()](../gtk4/method.Window.set_transient_for.html)
+ * if you’re using [GtkWindow](../gtk4/class.Window.html).
  */
 void
 gdk_toplevel_set_transient_for (GdkToplevel *toplevel,