Update theme for menus (#2578)

* Add radius to selected menu items, adust width to fit. Update colors.
* Fix server text color in chatview.

Signed-off-by: 3simplex <10260755+3Simplex@users.noreply.github.com>

gpt4all-chat/qml/ModelSettings.qml

@@ -62,7 +62,7 @@ MySettingsTab {
                     elide: Text.ElideRight
                 }
                 delegate: ItemDelegate {
-                    width: comboBox.width
+                    width: comboBox.width -20
                     contentItem: Text {
                         text: name
                         color: theme.textColor
@@ -71,7 +71,8 @@ MySettingsTab {
                         verticalAlignment: Text.AlignVCenter
                     }
                     background: Rectangle {
-                        color: highlighted ? theme.lightContrast : theme.darkContrast
+                        radius: 10
+                        color: highlighted ? theme.menuHighlightColor : theme.menuBackgroundColor
                     }
                     highlighted: comboBox.highlightedIndex === index
                 }