Reuse PM automatic route resolution and check persistence after successful send

tests/test_dm_invite.c

@@ -155,14 +155,14 @@ int main(void) {
         "BEGIN SELECT RAISE(ABORT,'test invite commit failure'); END", NULL, NULL, NULL) == SQLITE_OK, "install failed commit");
     request(4, target, source_id, 0);
     CHECK(wait_result(ua, 4, DM_INVITE_SEND_ERROR) && !message_count(), "failed commit returns error and rolls back PM");
-    uint64_t route = 0;
-    CHECK(!scalar(nodes[0], "SELECT group_id FROM dm_conversations LIMIT 1", &route) && route == source,
-          "member invitation restores the existing PM's source group route");
     CHECK(sqlite3_exec(nodes[0]->topo_sqlite_db, "DROP TRIGGER fail_invite", NULL, NULL, NULL) == SQLITE_OK, "remove failed commit");
 
     request(5, target, "", 0); /* из шапки существующей PM исходная группа не передаётся */
     request(4, target, "", 1); /* запоздалая отмена другой операции не отменяет текущую */
     CHECK(wait_result(ua, 5, DM_INVITE_OK) && message_count() == 1, "one invitation committed for fixed peer");
+    uint64_t route = 0;
+    CHECK(!scalar(nodes[0], "SELECT group_id FROM dm_conversations LIMIT 1", &route) && route == source,
+          "successful PM restores its automatically resolved shared group route");
     char conv[64], messages[8192]; size_t length = 0;
     snprintf(conv, sizeof(conv), "%llu", (unsigned long long)dm_derive_conv_id(nodes[0]->node_id, nodes[1]->node_id));
     deadline = get_time_tb() + 100000;