feat: add option to start server with --api_keys

[vansangpfiev]

Describe Your Changes

This pull request includes updates to the engine/main.cc file to add support for API keys configuration. The changes introduce a new command-line argument for specifying API keys and handle the configuration update accordingly.

Key changes:

• Added a new command-line argument --api_keys to specify API keys in the print_help function.
• Introduced a new optional variable api_keys in the main function to store the API keys.
• Updated the command-line argument parsing logic to handle the --api_keys argument for both wide and narrow character strings. [1] [2]
• Added logic to update the Cortex configuration with the provided API keys if the --api_keys argument is specified.

Fixes Issues

• Closes #
• Closes #

Self Checklist

• Added relevant comments, esp in complex areas
• Updated docs (for bug fixes / features)
• Created issues for follow-up changes or refactoring needed