qml: add EMPTY state to ValueInput

The EMPTY state indicates that this setting hasn't been touched.
Clicking on the Setting that contains the ValueInput is enough to put
it in the FILLED state.

Author: jarolrod

src/qml/components/DeveloperOptions.qml

@@ -35,7 +35,10 @@ ColumnLayout {
                 dbcacheSetting.forceActiveFocus()
             }
         }
-        onClicked: loadedItem.forceActiveFocus()
+        onClicked: {
+            loadedItem.filled = true
+            loadedItem.forceActiveFocus()
+        }
     }
     Separator { Layout.fillWidth: true }
     Setting {
@@ -50,7 +53,10 @@ ColumnLayout {
                 parSetting.forceActiveFocus()
             }
         }
-        onClicked: loadedItem.forceActiveFocus()
+        onClicked: {
+            loadedItem.filled = true
+            loadedItem.forceActiveFocus()
+        }
     }
     Separator { Layout.fillWidth: true }
     Setting {

src/qml/components/StorageSettings.qml

@@ -41,6 +41,9 @@ ColumnLayout {
                 pruneTargetSetting.forceActiveFocus()
             }
         }
-        onClicked: loadedItem.forceActiveFocus()
+        onClicked: {
+            loadedItem.filled = true
+            loadedItem.forceActiveFocus()
+        }
     }
 }

src/qml/controls/ValueInput.qml

@@ -9,8 +9,9 @@ TextInput {
     id: root
     required property string parentState
     property string description: ""
+    property bool filled: false
     property int descriptionSize: 18
-    property color textColor: Theme.color.neutral9
+    property color textColor: root.filled ? Theme.color.neutral9 : Theme.color.neutral5
     enabled: true
     state: root.parentState
 
@@ -21,7 +22,10 @@ TextInput {
         },
         State {
             name: "HOVER"
-            PropertyChanges { target: root; textColor: Theme.color.orangeLight1 }
+            PropertyChanges {
+                target: root
+                textColor: root.filled ? Theme.color.orangeLight1 : Theme.color.neutral5
+            }
         },
         State {
             name: "DISABLED"