feat: KDocs 上传增强 + 离线监控 + Bug修复

KDocs 上传功能增强:
- 搜索优化：只用姓名搜索 + C列验证，避免匹配到错误单元格
- 有效行范围：支持配置起始行/结束行，限制上传区域
- 图片覆盖：支持覆盖单元格已有图片（Escape + Delete）
- 配置持久化：kdocs_row_start/row_end 保存到数据库（v18迁移）

二次登录功能:
- 登录后立即再次登录，让"上次登录时间"显示为刚刚

KDocs 离线监控:
- 每5分钟检测金山文档登录状态
- 离线时发送邮件通知管理员（每次掉线只通知一次）
- 恢复在线后重置通知状态

Bug 修复:
- 任务日志搜索账号关键词报错500：添加异常处理

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

db/admin.py

@@ -181,6 +181,8 @@ def get_system_config_raw() -> dict:
             "kdocs_image_column": "D",
             "kdocs_admin_notify_enabled": 0,
             "kdocs_admin_notify_email": "",
+            "kdocs_row_start": 0,
+            "kdocs_row_end": 0,
         }
 
 
@@ -209,6 +211,8 @@ def update_system_config(
     kdocs_image_column=None,
     kdocs_admin_notify_enabled=None,
     kdocs_admin_notify_email=None,
+    kdocs_row_start=None,
+    kdocs_row_end=None,
 ) -> bool:
     """更新系统配置（仅更新DB，不做缓存处理）。"""
     allowed_fields = {
@@ -235,6 +239,8 @@ def update_system_config(
         "kdocs_image_column",
         "kdocs_admin_notify_enabled",
         "kdocs_admin_notify_email",
+        "kdocs_row_start",
+        "kdocs_row_end",
         "updated_at",
     }
 
@@ -312,6 +318,12 @@ def update_system_config(
         if kdocs_admin_notify_email is not None:
             updates.append("kdocs_admin_notify_email = ?")
             params.append(kdocs_admin_notify_email)
+        if kdocs_row_start is not None:
+            updates.append("kdocs_row_start = ?")
+            params.append(kdocs_row_start)
+        if kdocs_row_end is not None:
+            updates.append("kdocs_row_end = ?")
+            params.append(kdocs_row_end)
 
         if not updates:
             return False

db/migrations.py

@@ -87,6 +87,9 @@ def migrate_database(conn, target_version: int) -> None:
     if current_version < 17:
         _migrate_to_v17(conn)
         current_version = 17
+    if current_version < 18:
+        _migrate_to_v18(conn)
+        current_version = 18
 
     if current_version != int(target_version):
         set_current_version(conn, int(target_version))
@@ -728,3 +731,21 @@ def _migrate_to_v17(conn):
             print(f"  ✓ 添加 users.{field} 字段")
 
     conn.commit()
+
+
+def _migrate_to_v18(conn):
+    """迁移到版本18 - 金山文档上传：有效行范围配置"""
+    cursor = conn.cursor()
+
+    cursor.execute("PRAGMA table_info(system_config)")
+    columns = [col[1] for col in cursor.fetchall()]
+
+    if "kdocs_row_start" not in columns:
+        cursor.execute("ALTER TABLE system_config ADD COLUMN kdocs_row_start INTEGER DEFAULT 0")
+        print("  ✓ 添加 system_config.kdocs_row_start 字段")
+
+    if "kdocs_row_end" not in columns:
+        cursor.execute("ALTER TABLE system_config ADD COLUMN kdocs_row_end INTEGER DEFAULT 0")
+        print("  ✓ 添加 system_config.kdocs_row_end 字段")
+
+    conn.commit()

db/schema.py

@@ -224,6 +224,8 @@ def ensure_schema(conn) -> None:
             kdocs_image_column TEXT DEFAULT 'D',
             kdocs_admin_notify_enabled INTEGER DEFAULT 0,
             kdocs_admin_notify_email TEXT DEFAULT '',
+            kdocs_row_start INTEGER DEFAULT 0,
+            kdocs_row_end INTEGER DEFAULT 0,
             updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
         )
         """