Harden redemption flow and improve operational safety

.env.example

@@ -9,6 +9,7 @@ PORT=8000
 DEBUG=false
 
 # 数据库 (SQLite)
+# 默认 sqlite:///redemption.db 会落到 Flask 的 instance/redemption.db
 DATABASE_URL=sqlite:///redemption.db
 
 # Flask会话密钥 (建议使用随机长字符串)
@@ -30,4 +31,5 @@ DEFAULT_DOMAIN=yourtenant.onmicrosoft.com
 DEFAULT_PASSWORD=P@ssw0rd123!
 DEFAULT_USAGE_LOCATION=US
 DEFAULT_LICENSE_SKU=ENTERPRISEPACK
-FORCE_CHANGE_PASSWORD=true
+LICENSE_ASSIGNMENT_REQUIRED=false
+FORCE_CHANGE_PASSWORD=true