数据流

Telegram ──getUpdates──> ProxyManager (polling loop per bot)
                            │
                            ├── Management: trackChat() / saveMessage() ──> SQLite
                            ├── Proxy (push): POST update ──> Backend URL
                            │                    │
                            │                    └── webhook reply ──> Telegram API
                            │
                            ├── Long Poll: enqueue ──> UpdateQueue (ring buffer)
                            │                              │
                            │            Backend ──getUpdates──> /tgapi/ ──> dequeue
                            │
                            ├── Routing: match rules ──> send via Target Bot ──> Telegram
                            │                │
                            │                └── save mapping ──> route_mappings (SQLite)
                            │
                            └── Reverse Route: check mappings ──> reply via Source Bot
                                                                       (Source-NAT return)

Backend ──sendMessage──> /tgapi/ (API proxy) ──> Telegram API
                            │
                            └── capture response ──> saveMessage() ──> SQLite

Browser ──HTTP──> Server ──API──> Bot ──Bot API──> Telegram
                    │
                    └──queries──> SQLite (read)