Grid Inventory (#21931)

* Grid Inventory

* oh boy we keep cracking on

* auto insertion is kinda working? gross, too!

* pieces and proper layouts

* fix the sprites

* mousing over grid pieces... finally

* dragging deez nuts all over the screen

* eek!

* dragging is 90% less horrendous

* auto-rotating

* flatten

* Rotation at last

* fix rotation and change keybind for removing items.

* rebinding and keybinding

* wow! look at that! configurable with a button! cool!

* dragging is a bit cooler, eh?

* hover insert, my beloved

* add some grids for storage, fix 1x1 storages, fix multiple inputs at once

* el navigation

* oh yeah some stuff i forgor

* more fixes and QOL stuff

* the griddening

* the last of it (yippee)

* sloth review :)

Content.Shared/CCVar/CCVars.cs

@@ -1655,6 +1655,12 @@ namespace Content.Shared.CCVar
         public static readonly CVarDef<bool> ToggleWalk =
             CVarDef.Create("control.toggle_walk", false, CVar.CLIENTONLY | CVar.ARCHIVE);
 
+        /// <summary>
+        /// Whether or not the storage UI is static and bound to the hotbar, or unbound and allowed to be dragged anywhere.
+        /// </summary>
+        public static readonly CVarDef<bool> StaticStorageUI =
+            CVarDef.Create("control.static_storage_ui", true, CVar.CLIENTONLY | CVar.ARCHIVE);
+
         /*
          * UPDATE
          */