- Added connection state tracking (initialized, init_timer, timeout, retry_count)
- Implemented etcp_link_send_init() with proper packet formatting
- Configured retry timeouts (initial 50ms, double every 10, max 5000ms)
- Auto-start connection establishment for client links in etcp_link_new()
- Implemented etcp_connections_send() with connection initiation logic
- Created test_etcp_connection_init.c for testing handshake process