feat(runtime): add support loading configuration from .env file and environment variables

[chiangzeon]

https://github.com/agentscope-ai/agentscope-runtime-java/issues/70

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[xuehuitian45]

The current code looks good to me. It can be merged after making the following two changes:

1. Please remove the Lombok syntax used in AgentApp, as our coding standards do not allow the use of Lombok.
2. Please document the new functionality you've added in the cookbook, so that users can become aware of the new feature and understand how to use it.

[chiangzeon]

The current code looks good to me. It can be merged after making the following two changes:

1. Please remove the Lombok syntax used in AgentApp, as our coding standards do not allow the use of Lombok.
2. Please document the new functionality you've added in the cookbook, so that users can become aware of the new feature and understand how to use it.

Okay, I am done

[xuehuitian45]

Please fix license error.

[chiangzeon]

Please fix license error.

Done

[xuehuitian45]

LGTM