修复数据库迁移问题、新增环境变量读写

pkg/conf/appmeta.py

@@ -1,3 +1,9 @@
+import os
+from dotenv import load_dotenv
+from pkg.log import log
+
+load_dotenv()
+
 APP_NAME = 'DiskNext Server'
 summary = '一款基于 FastAPI 的可公私兼备的网盘系统'
 description = 'DiskNext Server 是一款基于 FastAPI 的网盘系统，支持个人和企业使用。它提供了高性能的文件存储和管理功能，支持多种认证方式。'
@@ -7,6 +13,18 @@ BackendVersion = "0.0.1"
 
 IsPro = False
 
+debug: bool = os.getenv("DEBUG", "false").lower() in ("true", "1", "yes")
+
+if debug:
+    log.info("Debug mode is enabled. This is not recommended for production use.")
+
+host: str = os.getenv("HOST", "0.0.0.0")
+port: int = int(os.getenv("PORT", 5213))
+
+log.info(f"Starting DiskNext Server {BackendVersion} on {host}:{port}")
+
+database_url: str = os.getenv("DATABASE_URL", "sqlite+aiosqlite:///disknext.db")
+
 tags_meta = [
     {
         "name": "site",