fix(chat): node online status race, WELCOME peer_needed off-by-one, JOIN missing proto byte

- node_put/node_update_verified: set online=1 on INSERT (nodes created when conn is UP)
- channel_peers_all: fix peer_needed calculation (atl byte was missing)
- cs_send_channel_join: add proto byte to address serialization matching all parsers

tools/chatgui-android/app/src/main/java/com/utun/chat/data/ConfigProvider.kt

@@ -291,6 +291,7 @@ class ConfigProvider(private val context: Context) {
             if (privKey.length == 64) appendLine("my_private_key=$privKey")
             appendLine("db_path=$dbDir")
             appendLine("db_sync_enabled=1")
+            appendLine("chatserver_enabled=1")
             appendLine()
             for (srv in servers) {
                 val family = if (srv.bindIp.contains(":")) "v6" else "v4"