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/integrations.rs

@@ -0,0 +1,18 @@
+mod support;
+
+#[path = "integrations/cleanup_test.rs"]
+mod cleanup_test;
+#[path = "integrations/confirm_test.rs"]
+mod confirm_test;
+#[path = "integrations/dismiss_test.rs"]
+mod dismiss_test;
+#[path = "integrations/generate_token_test.rs"]
+mod generate_token_test;
+#[path = "integrations/get_queue_test.rs"]
+mod get_queue_test;
+#[path = "integrations/get_tokens_test.rs"]
+mod get_tokens_test;
+#[path = "integrations/ingest_test.rs"]
+mod ingest_test;
+#[path = "integrations/revoke_token_test.rs"]
+mod revoke_token_test;