dm: прямой обмен сообщениями (DM) + soundtouch + архитектура звонков

- src/dm/: dm_core/dm_crypto/dm_mailbox — прямой обмен сообщениями (DM)
- lib/soundtouch-master/: vendored SoundTouch (изменение темпа/высоты аудио)
- doc/dm_arch.md, doc/chat_call_arch.md: архитектура DM и звонков
- tests: test_dm.c, test_dm_e2e.c
- chat: рефакторинг chat_* модулей, member_sync, invite_build
- chatgui/chatgui-android: синхронизация с новым API чата
- lib/u_async, debug_config, utun_instance: сопутствующие изменения

tools/chatcli

@@ -21,6 +21,10 @@
 #   create <name>                    create new channel
 #   invite_to <ch_id> <node_id> <pubkey_hex> <ip:port> [proto]
 #                                    invite a node to add our channel
+#   dm_start <node_id> [ch_id]       start direct chat (DM) with a group member
+#   dm_list                          list DM conversations
+#   dm_messages <conv_id> [count]    read DM messages (decrypted)
+#   dm_send <conv_id> <text>         send DM text message
 #   listen                           interactive event listener
 
 import sys, os, json, socket, struct
@@ -126,6 +130,24 @@ def cmd_invite_to(ch_id, node_id, pubkey, addr, proto=None):
         params["proto"] = int(proto)
     _req("invite_to", **params)
 
+def cmd_dm_start(node_id, ch=None):
+    params = {"node_id": node_id}
+    if ch:
+        params["ch"] = ch
+    _req("dm_start", **params)
+
+def cmd_dm_list():
+    _req("dm_list")
+
+def cmd_dm_messages(conv_id, count=None):
+    params = {"conv_id": conv_id}
+    if count:
+        params["count"] = int(count)
+    _req("dm_messages", **params)
+
+def cmd_dm_send(conv_id, text):
+    _req("dm_send", conv_id=conv_id, data=text)
+
 def cmd_listen():
     print(f"Listening on {DEFAULT_HOST}:{DEFAULT_PORT} (Ctrl+C to quit)")
     s = _connect()
@@ -149,6 +171,10 @@ def cmd_listen():
                 print(f"[{obj.get('ch','?')}] channel updated")
             elif evt == "invite_received":
                 print(f"INVITE: ch={obj.get('ch','?')} name={obj.get('ch_name','?')} from={obj.get('from_id','?')}")
+            elif evt == "dm_msg":
+                print(f"DM[{obj.get('conv','?')}] from={obj.get('author_id','?')}: new message")
+            elif evt == "dm_conv":
+                print(f"DM[{obj.get('conv','?')}] conversation updated")
             else:
                 print(json.dumps(obj, indent=2, ensure_ascii=False))
     except KeyboardInterrupt:
@@ -191,6 +217,10 @@ def main():
         elif cmd in ("connect","join"): cmd_connect(*args[1:2] if len(args) > 1 else (_die("usage: connect <utun://...>"),))
         elif cmd == "create":          cmd_create(*args[1:2] if len(args) > 1 else (_die("usage: create <name>"),))
         elif cmd == "invite_to":       cmd_invite_to(*args[1:6] if len(args) > 4 else (_die("usage: invite_to <ch_id> <node_id> <pubkey_hex> <ip:port> [proto]"),))
+        elif cmd == "dm_start":        cmd_dm_start(*args[1:3] if len(args) > 1 else (_die("usage: dm_start <node_id> [ch_id]"),))
+        elif cmd == "dm_list":         cmd_dm_list()
+        elif cmd in ("dm_messages","dm_msgs"): cmd_dm_messages(*args[1:3] if len(args) > 1 else (_die("usage: dm_messages <conv_id> [count]"),))
+        elif cmd == "dm_send":         cmd_dm_send(*args[1:3] if len(args) > 2 else (_die("usage: dm_send <conv_id> <text>"),))
         elif cmd == "listen":          cmd_listen()
         else:                          print(f"Unknown command: {cmd}\nUse --help for usage", file=sys.stderr); sys.exit(1)
     except socket.timeout: