Tame some ButtonTable users into re-using Buttontable instances if possible (#7166)

* QuickDictLookup, ImageViewer, NumberPicker: Smarter `update` that will re-use most of the widget's layout instead of re-instantiating all the things.
* SpinWidget/DoubleSpinWidget: The NumberPicker change above renders a hack to preserve alpha on these widgets almost unnecessary. Also fixed said hack to also apply to the center, value button.

* Button: Don't re-instantiate the frame in setText/setIcon when unnecessary (e.g., no change at all, or no layout change).
* Button: Add a refresh method that repaints and refreshes a *specific* Button (provided it's been painted once) all on its lonesome.

* ConfigDialog: Free everything that's going to be re-instatiated on update
 
* A few more post #7118 fixes:
  * SkimTo: Always flag the chapter nav buttons as vsync
  * Button: Fix the highlight on rounded buttons when vsync is enabled (e.g., it's now entirely visible, instead of showing a weird inverted corner glitch).
  * Some more heuristic tweaks in Menu/TouchMenu/Button/IconButton
* ButtonTable: fix the annoying rounding issue I'd noticed in #7054 ;).

* Enable dithering in TextBoxWidget (e.g., in the Wikipedia full view). This involved moving the HW dithering align fixup to base, where it always ought to have been ;).

* Switch a few widgets that were using "partial" on close to "ui", or, more rarely, "flashui". The intent being to limit "partial" purely to the Reader, because it has a latency cost when mixed with other refreshes, which happens often enough in UI ;).

* Minor documentation tweaks around UIManager's `setDirty` to reflect that change.

* ReaderFooter: Force a footer repaint on resume if it is visible (otherwise, just update it).
* ReaderBookmark: In the same vein, don't repaint an invisible footer on bookmark count changes.

frontend/ui/widget/iconbutton.lua

@@ -108,15 +108,38 @@ function IconButton:onTapIconButton()
         UIManager:forceRePaint()
         --UIManager:waitForVSync()
 
-        -- If the callback closed our parent (which may not always be the top-level widget, or even *a* window-level widget; e.g., the Home/+ buttons in the FM), we're done
-        if UIManager:getTopWidget() == self.show_parent or UIManager:isSubwidgetShown(self.show_parent) then
-            self.image.invert = false
+        self.image.invert = false
+        -- If the callback closed our parent (which may not always be the top-level widget, or even *a* window-level widget), we're done
+        local top_widget = UIManager:getTopWidget()
+        if top_widget == self.show_parent or UIManager:isSubwidgetShown(self.show_parent) then
+            -- If the callback popped up the VK, it prevents us from finessing this any further, so repaint the whole stack
+            if top_widget == "VirtualKeyboard" then
+                UIManager:waitForVSync()
+                UIManager:setDirty(self.show_parent, function()
+                    return "ui", self.dimen
+                end)
+                return true
+            end
+
+            -- If the callback popped up a modal above us, repaint the whole stack
+            if top_widget ~= self.show_parent and top_widget.modal and self.dimen:intersectWith(UIManager:getPreviousRefreshRegion()) then
+                UIManager:waitForVSync()
+                UIManager:setDirty(self.show_parent, function()
+                    return "ui", self.dimen
+                end)
+                return true
+            end
+
+            -- Otherwise, we can unhighlight it safely
             UIManager:widgetInvert(self.image, self.dimen.x + self.padding_left, self.dimen.y + self.padding_top)
             UIManager:setDirty(nil, function()
                 return "fast", self.dimen
             end)
-            --UIManager:forceRePaint()
+        else
+            -- Callback closed our parent, we're done
+            return true
         end
+        --UIManager:forceRePaint()
     end
     return true
 end