Fix visualization closing when cmd shortcut is pressed (#7798)

Fixes #7457

The issue was caused by the FRP logic that assumed we wanted to close the preview even if it wasn't opened in the first place.

https://github.com/enso-org/enso/assets/6566674/ceb4996b-c878-4ff1-8bca-7d2a0b817769

app/gui/view/graph-editor/src/component/node.rs

@@ -785,7 +785,9 @@ impl Node {
         frp::extend! { network
             output_hover <- model.output.on_port_hover.map(|s| s.is_on());
             visualization_hover <- bool(&model.visualization.on_event::<mouse::Out>(), &model.visualization.on_event::<mouse::Over>());
-            hovered_for_preview <- output_hover || visualization_hover;
+            is_preview <- visualization.view_state.map(|s| s.is_preview());
+            preview_hover <- visualization_hover.gate(&is_preview);
+            hovered_for_preview <- output_hover || preview_hover;
             // The debounce is needed for a case where user moves mouse cursor from output port to
             // visualization preview. Moving out of the port make `output_hover` emit `false`,
             // making `hovered_for_preview` false for a brief moment - and that moment would cause

app/gui/view/graph-editor/src/component/visualization/container.rs

@@ -125,11 +125,16 @@ impl ViewState {
         )
     }
 
-    /// Indicates whether the visualization is fullscreen mode.
+    /// Indicates whether the visualization is in fullscreen mode.
     pub fn is_fullscreen(&self) -> bool {
         matches!(self, ViewState::Fullscreen)
     }
 
+    /// Indicates whether the visualization is in preview mode.
+    pub fn is_preview(&self) -> bool {
+        matches!(self, ViewState::Preview { .. })
+    }
+
     /// Return a new state after considering (lack of) presence of the error.
     pub fn error_status_updated(mut self, new_has_error: bool) -> Self {
         if let Self::Enabled { has_error } | Self::Preview { has_error } = &mut self {