feat: #239 不同的用户类型在选择指派人时操作不同

lib/core/widgets/license_type_manager.dart

...ore/widgets/user_selector/assignee/assignee_provider.dart

...e/widgets/user_selector/assignee/assignee_repository.dart

...ets/user_selector/assignee/local_assignee_repository.dart

lib/core/widgets/user_selector/user_provider.dart

lib/core/widgets/user_selector/user_selector.dart

lib/core/widgets/user_selector/user_selector_model.dart

lib/modules/issues/issue_creation_model.dart

lib/modules/issues/issue_creation_page.dart

lib/modules/issues/issue_creation_view.dart

lib/modules/projects/group_details/subgroup_page.dart

.../group_details/subgroups/project/project_issues_page.dart

...projects/group_details/subgroups/subgroup_list_model.dart

.../projects/group_details/subgroups/subgroup_list_page.dart

...modules/projects/projects_selector/projects_selector.dart

pubspec.lock

test/long_clain_happy_path_tests/go_into_sub_group_page.dart

test/modules/issues/issue_creation_page_test.dart

...cts/group_details/subgroups/subgroup_list_model_test.dart

...ects/group_details/subgroups/subgroup_list_page_test.dart