Gui: Organize tree view preferences (#21867)

* feat #18649: Organize tree options in one single preference page
-Removed tree view related code from all DlgSettingsAdvanced files
-Added Font size and Item Background Padding to DlgSettingsUI

Co-authored-by: Tiago Cardoso <tiagomiguelcardoso@tecnico.ulisboa.pt>

* fix #18649: Organize tree options in one single preference page
-Added new line at the end of file DlgSettingsAdvanced.cpp
-Added new line at the end of file DlgSettingsAdvanced.py
-Added new line at the end of file DlgSettingsUI.ui
-Delete trailing space on file DlgSettingsAdvanced.py
-Delete extra line on file DlgSettingsAdvanced.h

Co-authored-by: Tiago Almeida <tiago.c.almeida@tecnico.ulisboa.pt>

* Gui: Remove over-advanced UI prefs

---------

Co-authored-by: Tiago Cardoso <tiagomiguelcardoso@tecnico.ulisboa.pt>
Co-authored-by: Chris Hennes <chennes@pioneerlibrarysystem.org>

src/Gui/PreferencePages/DlgSettingsUI.cpp

@@ -68,8 +68,8 @@ void DlgSettingsUI::saveSettings()
     ui->OverlayStyleSheets->onSave();
 
     // Tree View
+    ui->fontSizeSpinBox->onSave();
     ui->iconSizeSpinBox->onSave();
-    ui->rowSpacingSpinBox->onSave();
     ui->resizableColumnsCheckBox->onSave();
     ui->showVisibilityIconCheckBox->onSave();
     ui->hideDescriptionCheckBox->onSave();
@@ -97,8 +97,8 @@ void DlgSettingsUI::loadSettings()
     ui->ThemeAccentColor3->onRestore();
 
     // Tree View
+    ui->fontSizeSpinBox->onRestore();
     ui->iconSizeSpinBox->onRestore();
-    ui->rowSpacingSpinBox->onRestore();
     ui->resizableColumnsCheckBox->onRestore();
     ui->showVisibilityIconCheckBox->onRestore();
     ui->hideDescriptionCheckBox->onRestore();