[pixels-common] When there are no environment variables, the default location for the configuration file can easily lead to misunderstandings

[alph00]

When there are no environment variables, the default location for the configuration file can easily lead to misunderstandings. It would be helpful to add a prompt or directly refuse to start.

[bianhq]

You can add a warning to the log when the default config file path is to be used. Refuse to start (exit the process?) may be weird in some runtime environments.