- Add CreateGroupDialog with group name input
- Generate X25519+Ed25519 keypairs, random uint64 channel_id,
Ed25519 signature, write to DB via uasync thread
- chat_core_create_channel(): create msg table, topo_node_sqlite_channel_put()
- GUI_EVT_CHANNEL_UPDATED notification to reload channel list
- Per-category debug config: debug_level= + debug_categories= in [gui]
- Unified logging via debug_config: all threads write to same file/console
- debug_enable_console(1) to mirror file output to stderr
- DEBUG_LEVEL_DISABLED=-1: truly disable category, NONE=0 fallback to global
- Fix uasync_post under epoll: process_posted_tasks was never called
- Fix MainWindow constructor parameter ordering (dbPath vs debugFile)
- debug_ui.h: append mode ('a' instead of 'w')
Evgeny