Fix logging documentation (#226)

The logging documentation is buried in a code file, and it's wrong, so
this PR corrects that.

---------

Signed-off-by: Jared O'Connell <joconnel@redhat.com>
Co-authored-by: Mark Kurtz <mark.j.kurtz@gmail.com>

Author: jaredoconnell

DEVELOPING.md

@@ -267,6 +267,20 @@ Reference [https://www.npmjs.com/package/jest-runner-groups](jest-runner-groups)
  */
 ```
 
+### Logging
+
+Logging is useful for learning how GuideLLM works and finding problems.
+
+Logging is set using the following environment variables:
+
+- `GUIDELLM__LOGGING__DISABLED`: Disable logging (default: false).
+- `GUIDELLM__LOGGING__CLEAR_LOGGERS`: Clear existing loggers from loguru (default: true).
+- `GUIDELLM__LOGGING__CONSOLE_LOG_LEVEL`: Log level for console logging (default: none, options: DEBUG, INFO, WARNING, ERROR, CRITICAL).
+- `GUIDELLM__LOGGING__LOG_FILE`: Path to the log file for file logging (default: guidellm.log if log file level set else none)
+- `GUIDELLM__LOGGING__LOG_FILE_LEVEL`: Log level for file logging (default: INFO if log file set else none).
+
+If logging isn't responding to the environment variables, run the `guidellm config` command to validate that the environment variables match and are being set correctly.
+
 ## Additional Resources
 
 - [CONTRIBUTING.md](https://github.com/neuralmagic/guidellm/blob/main/CONTRIBUTING.md): Guidelines for contributing to the project.

src/guidellm/logger.py

@@ -9,13 +9,16 @@
     - GUIDELLM__LOGGING__DISABLED: Disable logging (default: false).
     - GUIDELLM__LOGGING__CLEAR_LOGGERS: Clear existing loggers
         from loguru (default: true).
-    - GUIDELLM__LOGGING__LOG_LEVEL: Log level for console logging
+    - GUIDELLM__LOGGING__CONSOLE_LOG_LEVEL: Log level for console logging
         (default: none, options: DEBUG, INFO, WARNING, ERROR, CRITICAL).
-    - GUIDELLM__LOGGING__FILE: Path to the log file for file logging
+    - GUIDELLM__LOGGING__LOG_FILE: Path to the log file for file logging
         (default: guidellm.log if log file level set else none)
-    - GUIDELLM__LOGGING__FILE_LEVEL: Log level for file logging
+    - GUIDELLM__LOGGING__LOG_FILE_LEVEL: Log level for file logging
         (default: INFO if log file set else none).
 
+If logging isn't responding to the environment variables, run the `guidellm config`
+command to validate that the environment variables match and are being set correctly.
+
 Usage:
     from guidellm import logger, configure_logger, LoggerConfig