Core: post-KivyMD cleanup (#4815)

* Removed now unused imports from Launcher
* Moved ImageIcon and ImageButton to use ApAsyncImage for compatibility with apworlds
* Adjusted image size in the Launcher from 40x40 to 48x48. This is already larger than the size in previous versions, and a docs update is soon to follow.
* Expose `dynamic_scheme_contrast` to user.kv, allowing users to set high contrast.
* ScrollBox's default scroll_type was set to only content, so the scrollbar in Launcher was nonfunctional.
* Adjusted the spacing of the title of a component when a description is present to be closer to the center.
* Launcher now scrolls to the top automatically when changing between filters

data/client.kv

@@ -18,6 +18,7 @@
     theme_style: "Dark" # Light/Dark
     primary_palette: "Green" # Many options
     dynamic_scheme_name: "TONAL_SPOT"
+    dynamic_scheme_contrast: 0.0
 <MDLabel>:
     color: self.theme_cls.primaryColor
 <TooltipLabel>:
@@ -184,6 +185,7 @@
     bar_width: "12dp"
     scroll_wheel_distance: 40
     do_scroll_x: False
+    scroll_type: ['bars', 'content']
 
     MDBoxLayout:
         id: layout

data/launcher.kv

@@ -9,13 +9,13 @@
     MDRelativeLayout:
         ApAsyncImage:
             source: main.image
-            size: (40, 40)
+            size: (48, 48)
             size_hint_y: None
             pos_hint: {"center_x": 0.1, "center_y": 0.5}
 
         MDLabel:
             text: main.component.display_name
-            pos_hint:{"center_x": 0.5, "center_y": 0.85 if main.component.description else 0.65}
+            pos_hint:{"center_x": 0.5, "center_y": 0.75 if main.component.description else 0.65}
             halign: "center"
             font_style: "Title"
             role: "medium"