dark mode feature

Author: Veeransh14

ui/kiwixconfirmbox.ui

@@ -142,7 +142,7 @@
        </property>
       </widget>
      </item>
-     <item>
+     <item> <!--added checkbox -->
       <widget class="QCheckBox" name="darkModeCheckbox">
        <property name="text">
         <string>Dark Mode</string>

ui/localkiwixserver.ui

@@ -123,7 +123,7 @@
       </size>
      </property>
      <property name="currentIndex">
-      <number>0</number>
+      <number>2</number>
      </property>
      <widget class="QWidget" name="StartServerOptions">
       <layout class="QHBoxLayout" name="horizontalLayout_2">
@@ -182,6 +182,17 @@
        </item>
       </layout>
      </widget>
+     <widget class="QWidget" name="DarkModeOptions">
+      <layout class="QHBoxLayout" name="horizontalLayout_4">
+       <item>
+        <widget class="QCheckBox" name="darkModeCheckbox">
+         <property name="text">
+          <string>Dark Mode</string>
+         </property>
+        </widget>
+       </item>
+      </layout>
+     </widget>
     </widget>
    </item>
    <item row="1" column="0" colspan="3">