test(chat): give diagnostic links a valid empty ACK queue

tests/test_chat_member.c

@@ -214,7 +214,10 @@ static void details(struct UTUN_INSTANCE* inst) {
 static void diagnostics(struct UTUN_INSTANCE* inst) {
     struct ETCP_CONN connection = {.instance = inst, .peer_node_id = 9, .unacked_bytes = UINT32_MAX};
     struct ETCP_LINK* links = u_calloc(300, sizeof(*links)); assert(links); connection.links = links;
-    for (int i = 0; i < 300; i++) { links[i].etcp = &connection; links[i].next = i < 299 ? links + i + 1 : NULL; }
+    struct ll_queue* acks = queue_new(inst->ua, 0, 0, 0, "member_test_acks"); assert(acks);
+    for (int i = 0; i < 300; i++) {
+        links[i].etcp = &connection; links[i].ack_q = acks; links[i].next = i < 299 ? links + i + 1 : NULL;
+    }
     struct ll_entry* entry = queue_entry_new(sizeof(struct conn_queue_entry)); assert(entry);
     struct conn_queue_entry* item = (struct conn_queue_entry*)entry->data; item->peer_node_id = 9; item->conn = &connection;
     assert(!queue_data_put_with_index(inst->connections, entry)); expect_large_text = 1; unsigned before = text_events;
@@ -223,7 +226,7 @@ static void diagnostics(struct UTUN_INSTANCE* inst) {
     assert(text_events == before + 2);
     target = "strbuf.c"; fault = F_REALLOCATE; chat_core_collect_status_trampoline(inst); assert(fault == F_NONE && text_events == before + 2);
     chat_core_collect_status_trampoline(inst); assert(text_events == before + 3); expect_large_text = 0;
-    queue_remove_data(inst->connections, entry); queue_entry_free(entry); u_free(links);
+    queue_remove_data(inst->connections, entry); queue_entry_free(entry); u_free(links); queue_free(acks);
     if (SIZE_MAX > UINT32_MAX) {
         size_t baseline = u_get_allocated_count(); struct strbuf text; strbuf_init(&text, (size_t)UINT32_MAX + 1);
         assert(!text.buf && !text.cap && !text.len && u_get_allocated_count() == baseline);