Remove direct dependencies on makepad-test and use the re-exported
version from makepad-widgets instead. This avoids path dependency
issues and follows the correct pattern for using Makepad crates.
Changes:
- Add 'test' feature to makepad-widgets dependencies
- Remove direct makepad-test dependencies
- Update imports to use makepad_widgets::makepad_test
Affected crates:
- crates/apps/map
- crates/apps/pdf/pdf-makepad
- crates/apps/spreadsheet/spreadsheet-ui
