重构后端，改为 node 技术栈

backend/.env.example

@@ -1,10 +1,38 @@
 # Database Configuration
-DATABASE_HOST=localhost
+DATABASE_HOST=192.168.9.137
 DATABASE_PORT=3306
 DATABASE_NAME=audio
 DATABASE_USER=root
-DATABASE_PASSWORD=root1
+DATABASE_PASSWORD=root123
 
 # Application Settings
 APP_NAME=Audio Dashboard API
 DEBUG=True
+PORT=8083
+
+# JWT
+JWT_SECRET=dev-only-change-me-for-production
+DASHBOARD_ADMIN_USERNAME=admin
+DASHBOARD_ADMIN_PASSWORD=Eafon123
+
+# Meilisearch
+MEILISEARCH_URL=http://localhost:7700
+MEILISEARCH_API_KEY=
+MEILISEARCH_INDEX=models
+
+# AWS S3 (OTA X8)
+AWS_REGION=eu-central-1
+AWS_ACCESS_KEY_ID=
+AWS_SECRET_ACCESS_KEY=
+AWS_S3_OTA_BUCKET=luxsin-app-bucket
+
+# OTA URLs
+OTA_X8_PUBLIC_BASE=http://am.luxsinaudio.com
+OTA_X9_URL_BASE=http://source.luxsin.net
+
+# OTA Upload Directories
+OTA_UPLOAD_DIR_DEV=
+OTA_UPLOAD_DIR_PROD=/data/project/dashboard/upload
+
+# File Upload
+UPLOAD_FOLDER=/data/project/autoeq/measurements