Updated documentations for running locally using Docker-Compose.

[MefhigosetH]

Add Docker Compose Documentation and Example Configuration

This PR introduces documentation and an example configuration for deploying livekit-sip using Docker Compose. The changes aim to streamline the setup process, making it easier for developers and users to quickly get started with the project in a containerized environment. Related to issue https://github.com/livekit/sip/issues/267#issue-2806627392

Changes Included:

• Added a new section for Docker Compose setup.
• Added detailed instructions on how to set up and run livekit-sip using Docker Compose.
• Includes steps for configuration, running the services, and troubleshooting common issues.
• Linked relevant files and provided usage tips.

Why These Changes?

• Ease of Use: Simplifies the deployment process for users who prefer containerized setups.
• Improved Accessibility: Reduces the learning curve for new users by providing ready-to-use configurations.
• Standardization: Encourages consistent setup and deployment practices across different environments.

Feedback Welcome:

• Suggestions for improving the documentation clarity.
• Testing feedback on the provided Docker Compose configuration.
• Additional use cases or edge cases that should be covered in the examples.