- Remove is_dm column from channels table (dm detection by member count)
- Rename member name column to userinfo — extensible json_flat format
- Add json_flat.c/h library for compact JSON serialization
- Fix join_sig message format: use ch_x25519+ch_ed25519 instead of channel_id string
- Remove name from join_msg body (now in userinfo via json_flat)
- Update chat_core, chat_sync, member_sync, db_manager to new format
- Add topo_strategy.txt — архитектурные заметки по топологии
- chat_core_sync_my_addresses: DELETE + INSERT с подсчётом строк, CHECK verify
- chat_core_connect_from_invite: DELETE + INSERT с IP:port
- member_sync_put: DELETE + INSERT с IP:port, warn если addrs_data=NULL
- cs_handle_channel_info_resp: адрес инвайтера из ETCP link
- cs_handle_channel_join: адреса джойнера
- cs_handle_peer_upsert: адреса пира
- cs_handle_welcome: адреса из WELCOME
Все логи с префиксом [ADDR_SYNC] в DEBUG_CATEGORY_DEBUG
- topo_sqlite_db moved from TOPO_GROUPS to UTUN_INSTANCE (direct access)
- topo_groups_set_sqlite_db() removed
- chatgui: chat_sync_connect_node → chat_core_connect_auto (direct ETCP, no conn_mgr)
- chatgui: chat_core_connect_from_invite saves to SQLite → auto connect (no BGP)
- chatgui: removed _on_node_updated BGP callback from member_sync
- chatgui: removed conn_mgr_get_status from status dump
- chatgui: removed all conn_mgr.h and topo_group.h includes
- chatgui: CONN_MGR_ERR_* constants → CC_* in chat_core.h
- removed unused cc_parallel_* code, conn_state_str/conn_type_str helpers
Evgeny