fix: resolve environment variable escaping issues in docker-compose.yml

[ianZzzzzz]

修复内容：

1. 修正 mysql 和 elasticsearch 服务中的环境变量转义问题（$${VAR} → $$${VAR}）
2. 优化服务依赖逻辑，移除冗余依赖项
3. 补充缺失的环境变量默认值

问题描述：
原配置在启动时会触发以下错误：

• invalid interpolation format for services.mysql.healthcheck
• invalid interpolation format for services.elasticsearch.command

修复依据：
根据 Docker Compose 官方文档，容器内的环境变量引用需使用 $$${VAR} 格式转义。

Fix Content

1. Fix environment variable escaping issues in mysql and elasticsearch services (change $${VAR} to $$${VAR})
2. Optimize service dependency logic by removing redundant dependencies
3. Add default values for missing environment variables

Problem Description

The original configuration triggers the following errors during startup:

• invalid interpolation format for services.mysql.healthcheck
• invalid interpolation format for services.elasticsearch.command

Fix Basis

According to the official Docker Compose documentation, environment variable references inside containers must use the $$${VAR} format for proper escaping.

[CLAassistant]

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[fanlv]

rebase 下。测试下，没问题我给你合。