Misc: made ImGuiDir, ImGuiSortDirection, ImGuiMouseCursor stronger-typed enums + cater for possible warning in backends's switch()

Not making ImGuiMouseCursor one because of warnings for non-explicitly handled value (case default: is not enough).

imgui_internal.h

@@ -1582,6 +1582,7 @@ enum ImGuiNavLayer
     ImGuiNavLayer_COUNT
 };
 
+// Storage for navigation query/results
 struct ImGuiNavItemData
 {
     ImGuiWindow*        Window;         // Init,Move    // Best candidate window (result->ItemWindow->RootWindowForNav == request->Window)
@@ -1598,6 +1599,7 @@ struct ImGuiNavItemData
     void Clear()        { Window = NULL; ID = FocusScopeId = 0; InFlags = 0; SelectionUserData = -1; DistBox = DistCenter = DistAxial = FLT_MAX; }
 };
 
+// Storage for PushFocusScope()
 struct ImGuiFocusScopeData
 {
     ImGuiID             ID;
@@ -2516,6 +2518,7 @@ struct IMGUI_API ImGuiWindow
     int                     NameBufLen;                         // Size of buffer storing Name. May be larger than strlen(Name)!
     ImGuiID                 MoveId;                             // == window->GetID("#MOVE")
     ImGuiID                 ChildId;                            // ID of corresponding item in parent window (for navigation to return from child window to parent window)
+    ImGuiID                 PopupId;                            // ID in the popup stack when this window is used as a popup/menu (because we use generic Name/ID for recycling)
     ImVec2                  Scroll;
     ImVec2                  ScrollMax;
     ImVec2                  ScrollTarget;                       // target scroll position. stored as cursor position with scrolling canceled out, so the highest point is always 0.0f. (FLT_MAX for no change)
@@ -2542,7 +2545,6 @@ struct IMGUI_API ImGuiWindow
     short                   BeginOrderWithinParent;             // Begin() order within immediate parent window, if we are a child window. Otherwise 0.
     short                   BeginOrderWithinContext;            // Begin() order within entire imgui context. This is mostly used for debugging submission order related issues.
     short                   FocusOrder;                         // Order within WindowsFocusOrder[], altered when windows are focused.
-    ImGuiID                 PopupId;                            // ID in the popup stack when this window is used as a popup/menu (because we use generic Name/ID for recycling)
     ImS8                    AutoFitFramesX, AutoFitFramesY;
     bool                    AutoFitOnlyGrows;
     ImGuiDir                AutoPosLastDirection;