Write unit and integration tests for consent lifecycle

The atomicity test for revokeConsent requires careful mock design: inject a SupabaseException after the consent status update but before the location row deletion, then assert that the service either rolls both back or surfaces a CascadeDeleteFailure. Since Supabase RLS cannot be exercised in a real unit test, create a RlsPolicySimulator class that mirrors the policy logic in Dart so it can be tested in-process. For widget tests, use pumpWidget with a BlocProvider wrapping a fake ConsentBloc stub — do not spin up the real BLoC. Coverage gaps most likely hide in error paths (network timeout, malformed JSON from Supabase); ensure each failure class has at least one test.

Keep test file names mirroring the source file they cover to simplify navigation.

Use flutter_test for all unit and widget tests. Create a FakeSupabaseClient or use mocktail to stub all Supabase calls — no live Supabase connection in tests. Organize tests in three files: location_consent_service_test.dart (unit), consent_rls_policy_test.dart (integration-style with mocked RLS), and consent_dialog_widget_test.dart (widget). Use setUp/tearDown to reset state between cases.

Run coverage with `flutter test --coverage` and enforce the 90% branch threshold in CI via lcov. Test all four ConsentStatus enum values explicitly. For the atomicity test, inject a fault into the mock after the first DB write and assert rollback behavior.