feat(server): implement chat file TTL cleanup and enhance JPush vendor channel support

Add FileCleanupWorker for automatic expiration of chat files with configurable retention period and batch processing. Files uploaded via `/api/v1/uploads/files` are tracked in `uploaded_files` table with expiration timestamps, then deleted from S3 and database upon expiry. Expired file URLs are injected as `"expired": true` in message responses.

Extend JPush push notification configuration with vendor-specific channel_id support (xiaomi, huawei, oppo, vivo, meizu, honor, fcm) for differentiating system vs chat notifications. Add iOS APNs thread-id grouping configuration for notification categorization.

configs/config.yaml

@@ -288,11 +288,54 @@ report:
 # 极光推送配置
 # 环境变量:
 #   APP_JPUSH_ENABLED, APP_JPUSH_APP_KEY, APP_JPUSH_MASTER_SECRET, APP_JPUSH_PRODUCTION
+#   厂商通道 channel_id（区分系统消息与私聊消息，通过 options.third_party_channel 下发）:
+#     APP_JPUSH_CHANNEL_SYSTEM, APP_JPUSH_CHANNEL_CHAT
+#     APP_JPUSH_CHANNEL_XIAOMI_SYSTEM,  APP_JPUSH_CHANNEL_XIAOMI_CHAT
+#     APP_JPUSH_CHANNEL_HUAWEI_SYSTEM,  APP_JPUSH_CHANNEL_HUAWEI_CHAT
+#     APP_JPUSH_CHANNEL_OPPO_SYSTEM,    APP_JPUSH_CHANNEL_OPPO_CHAT
+#     APP_JPUSH_CHANNEL_VIVO_SYSTEM,    APP_JPUSH_CHANNEL_VIVO_CHAT
+#     APP_JPUSH_CHANNEL_MEIZU_SYSTEM,   APP_JPUSH_CHANNEL_MEIZU_CHAT
+#     APP_JPUSH_CHANNEL_HONOR_SYSTEM,   APP_JPUSH_CHANNEL_HONOR_CHAT
+#     APP_JPUSH_CHANNEL_FCM_SYSTEM,     APP_JPUSH_CHANNEL_FCM_CHAT
+#   小米消息模板（可选，配置后私信消息携带 channel_id 与 mi_template_id）:
+#     APP_JPUSH_CHANNEL_XIAOMI_MI_SYSTEM_TEMPLATE_ID, APP_JPUSH_CHANNEL_XIAOMI_MI_CHAT_TEMPLATE_ID
+#   OPPO 私信模板（可选，仅 OPPO，配置后下发私信时携带）:
+#     APP_JPUSH_CHANNEL_OPPO_SYSTEM_PRIVATE_TEMPLATE_ID, APP_JPUSH_CHANNEL_OPPO_CHAT_PRIVATE_TEMPLATE_ID
+#   iOS 通知分组 thread-id:
+#     APP_JPUSH_CHANNEL_IOS_CHAT_THREAD_ID, APP_JPUSH_CHANNEL_IOS_SYSTEM_THREAD_ID
 jpush:
   enabled: false
   app_key: ""
   master_secret: ""
   production: false  # true: 生产环境, false: 开发环境
+  # 厂商通道 channel_id 配置（全部可选，留空则不下发对应厂商字段）
+  # channel.system / channel.chat 为各厂商默认 channel_id
+  # channel.vendor.{vendor}.{system|chat} 可单独覆盖某厂商，留空则回退到默认值
+  #   小米/OPPO 额外支持消息模板 id（按场景区分），配置后私信消息下发时携带
+  #   其余厂商（华为/VIVO/魅族/荣耀/FCM）仅 channel_id
+  channel:
+    system: ""   # 系统消息/通知默认 channel_id
+    chat: ""     # 私聊/群聊消息默认 channel_id
+    vendor:
+      xiaomi:
+        system: ""
+        chat: ""
+        mi_system_template_id: ""   # 小米系统消息模板 id
+        mi_chat_template_id: ""     # 小米私聊消息模板 id
+      huawei: { system: "", chat: "" }
+      oppo:
+        system: ""
+        chat: ""
+        oppo_system_private_template_id: ""  # OPPO 系统消息私信模板 id
+        oppo_chat_private_template_id: ""    # OPPO 私聊消息私信模板 id
+      vivo:   { system: "", chat: "" }
+      meizu:  { system: "", chat: "" }
+      honor:  { system: "", chat: "" }
+      fcm:    { system: "", chat: "" }
+    # iOS APNs 通知分组（按 thread-id 区分系统/私聊通知，不配置则不分组）
+    ios:
+      chat_thread_id: ""    # 私聊/群聊通知分组 thread-id
+      system_thread_id: ""  # 系统消息/通知分组 thread-id
 
 # 初始化超级管理员密钥
 # 环境变量: APP_SETUP_SECRET