feat(ui): full‑width ShadTable across app; fix rent dialog width; correct equipment pagination

- ShadTable: ensure full-width via LayoutBuilder+ConstrainedBox minWidth
- BaseListScreen: default data area padding = 0 for table edge-to-edge
- Vendor/Model/User/Company/Inventory/Zipcode: set columnSpanExtent per column
  and add final filler column to absorb remaining width; pin date/status/actions
  widths; ensure date text is single-line
- Equipment: unify card/border style; define fixed column widths + filler;
  increase checkbox column to 56px to avoid overflow
- Rent list: migrate to ShadTable.list with fixed widths + filler column
- Rent form dialog: prevent infinite width by bounding ShadProgress with
  SizedBox and remove Expanded from option rows; add safe selectedOptionBuilder
- Admin list: fix const with non-const argument in table column extents
- Services/Controller: remove hardcoded perPage=10; use BaseListController
  perPage; trust server meta (total/totalPages) in equipment pagination
- widgets/shad_table: ConstrainedBox(minWidth=viewport) so table stretches

Run: flutter analyze → 0 errors (warnings remain).

test/integration/automated/pagination_test.dart

@@ -110,7 +110,7 @@ class PaginationTest {
         'page': 1,
         'perPage': 5,
         'count': page1.items.length,
-        'firstItem': page1.items.isNotEmpty ? page1.items.first.name : null,
+        'firstItem': page1.items.isNotEmpty ? page1.items.first.serialNumber : null,
       });
       
       // 2. 두 번째 페이지 조회
@@ -583,4 +583,4 @@ void main() async {
       await tester.runAllTests();
     }, timeout: Timeout(Duration(minutes: 10)));
   });
-}
+}