test: move application tests to tests/

test_support/test_helpers -> tests/support; watched_at unified w/ domain test_watched_at (2024-03-15).
Kept inline: users::diary_filter tests (feed_sort_to_direction_all_variants, paged_user_filter_builds_correctly) - pub(super) helpers in private module.
Dropped stale never-compiled users/tests/get_users.rs (old execute signature).

crates/application/tests/import.rs

@@ -0,0 +1,26 @@
+mod support;
+
+#[path = "import/apply_mapping_test.rs"]
+mod apply_mapping_test;
+#[path = "import/apply_profile_and_map_test.rs"]
+mod apply_profile_and_map_test;
+#[path = "import/apply_profile_test.rs"]
+mod apply_profile_test;
+#[path = "import/cleanup_test.rs"]
+mod cleanup_test;
+#[path = "import/create_session_test.rs"]
+mod create_session_test;
+#[path = "import/delete_profile_test.rs"]
+mod delete_profile_test;
+#[path = "import/execute_test.rs"]
+mod execute_test;
+#[path = "import/get_mapping_stage_test.rs"]
+mod get_mapping_stage_test;
+#[path = "import/get_preview_stage_test.rs"]
+mod get_preview_stage_test;
+#[path = "import/get_session_state_test.rs"]
+mod get_session_state_test;
+#[path = "import/list_profiles_test.rs"]
+mod list_profiles_test;
+#[path = "import/save_profile_test.rs"]
+mod save_profile_test;