Use structured logging framework

Replace all console.* calls with an appropriate structured logging framework using proper log levels. This ensures consistent logging patterns, better log management, and appropriate handling of different severity levels.

Key guidelines:

• Use logger.debug() for development/troubleshooting information
• Use logger.info() for general operational information
• Use logger.warn() for concerning but non-critical issues
• Use logger.error() for critical issues and errors
• Pass objects directly to logger instead of string interpolation

Example:

// Don't do this:
console.log("Processing batch:", JSON.stringify(batch));
console.warn("Redis client not available");
console.error("Failed to process:", error);

// Do this instead:
logger.info("Processing batch", { batch });
logger.warn("Redis client not available");
logger.error("Failed to process", { error });

This approach provides better log management, filtering capabilities, and consistent logging patterns across the codebase.