fix(super-editor): re-export ContentControlViewportAddress and ViewportEntityAddress (SD-3156) (#3316)

The public `superdoc/ui` barrel (`packages/superdoc/src/ui.d.ts`) imports both names from `@superdoc/super-editor/ui`, but they were missing from `packages/super-editor/src/ui/index.ts`. The existing `ui.barrel.test.ts` only string-scans the barrel file, so it didn't catch the upstream gap.

CI's consumer-typecheck matrix (`bundler | node16 | nodenext` with `skipLibCheck=false`) was failing with TS2305 on both names since #3310 landed.

Author: caio-pizzol

packages/super-editor/src/ui/index.ts

@@ -124,8 +124,10 @@ export type {
   TrackChangesSlice,
 
   // Viewport
+  ContentControlViewportAddress,
   ViewportContext,
   ViewportContextAtInput,
+  ViewportEntityAddress,
   ViewportEntityAtInput,
   ViewportEntityHit,
   ViewportGetRectInput,