Inconsistent container name between `lstk` (`localstack-aws`) and MCP (`localstack-main`)

When running lstk for the first time, it sets up a Docker container named localstack-aws. However, the MCP currently searches for a container named localstack-main by default.

This mismatch can be confusing for new users and makes onboarding harder. It would be helpful to standardize the container name between lstk and the MCP (e.g., both using either localstack-aws or localstack-main), or to document the difference clearly.

未指定文件或测试。首先跟踪 lstk 首次运行时的容器设置以及 MCP 的默认容器查找，然后决定是统一使用一个名称，还是记录这一差异。完成标准是两个路径使用一致的容器名称，或明确记录这一差异。