Define INFO-only stream probes and provider offer snapshots

src/stream/stream_network.h

@@ -24,7 +24,17 @@ struct stream_receive_info {
     struct stream_metric_snapshot metrics, supplier_metrics;
     uint32_t rtt_ms;
     int metrics_valid, supplier_metrics_valid, rtt_valid, close_requested;
+    struct stream_path path;
+    uint64_t first_available, last_available, info_ms, supplier_queue_bytes, progress_age_ms;
+    uint32_t path_rtt_ms;
+    uint16_t free_slots, cpu_basis_points;
+    uint8_t subblock;
+    int info_ready, probe_only, accepting, path_rtt_valid, progress_valid, cpu_valid;
 };
+/* INFO без выделения remote handle и без DATA; close обязателен также после detach.
+ * После ready можно тем же NCD-владением последовательно опросить остальные субпотоки. */
+int stream_probe_open(struct STREAM_HANDLE *subscription, uint64_t peer, uint8_t subblock, struct STREAM_RECEIVE **out);
+int stream_probe_next(struct STREAM_RECEIVE *probe, uint8_t subblock);
 /* out заранее NULL; seq=UINT64_MAX: первая выдача с конца, остальные ждут её проверенный общий старт.
  * peer должен быть онлайн-кандидатом группы. Повтор peer+stream+sub не создаёт вторую выдачу. */
 int stream_receive_open(struct STREAM_HANDLE *subscription, uint64_t peer, uint8_t subblock, uint64_t seq, struct STREAM_RECEIVE **out);

src/stream/stream_wire.h

@@ -10,14 +10,15 @@
 extern "C" {
 #endif
 
-#define STREAM_WIRE_VERSION 2
+#define STREAM_WIRE_VERSION 3
 #define STREAM_WIRE_HEADER 52
 #define STREAM_PATH_MAX 32
 #define STREAM_END_SIZE 106
 #define STREAM_METRIC_WIRE_SIZE 49
 #define STREAM_INFO_METRIC_OFF 36
-#define STREAM_INFO_PATH_OFF (STREAM_INFO_METRIC_OFF + STREAM_METRIC_WIRE_SIZE)
-#define STREAM_INFO_SIZE (STREAM_INFO_PATH_OFF + 1) /* probe:8, границы/FEC:28, метрики:49, count:1 */
+#define STREAM_INFO_OFFER_OFF (STREAM_INFO_METRIC_OFF + STREAM_METRIC_WIRE_SIZE)
+#define STREAM_INFO_PATH_OFF (STREAM_INFO_OFFER_OFF + 25)
+#define STREAM_INFO_SIZE (STREAM_INFO_PATH_OFF + 1) /* probe:8, границы/FEC:28, метрики:49, предложение:25, count:1 */
 #define STREAM_OVERLOAD_MAX 64
 #define STREAM_OVERLOAD_HEADER 18