Revise the first-boot script to implement a structured approach with 13 numbered steps, allowing for better control over the execution order. Introduce two new one-shot scripts: `01-set-rotation-once.sh` and `02-set-wallpaper-once.sh`, replacing the previous single script approach. Update documentation to reflect these changes, including the new configuration options for enabling/disabling steps and the revised file structure for one-shot scripts. Enhance the dashboard to display first-boot progress, improving user feedback during the initial setup.