feat: multi-user support - Config format: JSON with bot_token (global), users array - Each user has chat_id, AI config, email_accounts - Each email account has separate IMAP/SMTP with ssl/starttls - Config module: new dataclasses (UserConfig, ImapConfig, SmtpConfig) - find_user_by_chat_id() for callback dispatch - Main: email poller iterates all users, queues carry user object - Summarizer: accepts UserConfig, uses user-specific AI and chat_id - TG bot: all functions use bot_token string instead of TelegramConfig - Callback/message handlers look up user by chat_id - AI regen/hint threads use find_user_by_chat_id for AI config - Config example: config.example.json - Tests: 3/3 passing

config.example.json

@@ -0,0 +1,32 @@
+{
+  "bot_token": "your_bot_token_here",
+  "polling_interval": 30,
+  "users": [
+    {
+      "chat_id": "your_telegram_chat_id",
+      "ai": {
+        "api_key": "your_deepseek_api_key",
+        "model": "deepseek-v4-flash",
+        "base_url": "https://api.deepseek.com"
+      },
+      "email_accounts": [
+        {
+          "username": "you@126.com",
+          "password": "your_imap_password",
+          "imap": {
+            "server": "imap.126.com",
+            "port": 993,
+            "ssl": true,
+            "starttls": false
+          },
+          "smtp": {
+            "server": "smtp.126.com",
+            "port": 465,
+            "ssl": true,
+            "starttls": false
+          }
+        }
+      ]
+    }
+  ]
+}