Count: Invalid Area dialog, table block kept with the table

- When the count area's boundary is gone the approved Invalid Area dialog
  asks: undo the change (also its X and Cancel) or count all of model space;
  "always" keeps the choice in the settings. An edited boundary moves the area.
- A table's *T block is brought up to date whenever the table changes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app/mod.rs

@@ -1943,6 +1943,7 @@ pub enum ModalKind {
     GeometricTolerance,
     AttDef,
     AttDefEdit,
+    CountInvalidArea,
     Field,
     DraftingSettings,
     AutoConstrainSettings,