fix(logging): complete logging system gaps across SDK, server, CLI, a…

[wayyoungboy]

…nd MCP

• Use module-level logger instead of root logger in 6 LLM integration modules
• Add exc_info=True to ~100 logger.error() calls in agent layer except blocks
• Attach TraceContextFilter to server and uvicorn loggers for request tracing
• Replace plain FileHandler with CompressingRotatingFileHandler in audit logger
• Make server log rotation configurable via POWERMEM_SERVER_LOG_MAX_SIZE env var
• Add JSON logging mode (LOGGING_FORMAT=json) to SDK via JsonLogFormatter
• Share single file handler across uvicorn loggers to prevent rotation races
• Replace traceback.print_exc() with logger.exception() in CLI commands
• Export all fields from LoggingSettings.to_config() and AuditSettings.to_config()
• Add module logger to MCP server

[lightzt99]

LGTM