Added a note on core.efi prefix limitation and guidance for multi-environment subdirectory PXE setups.
Clarified Secure Boot scope to UEFI-based architectures only, documented architecture-specific limitation of the shim package, and updated signed EFI file sourcing guidance.
Clarified that TFTP is mandatory for ppc64le and that the loader
subdirectory in the installation media may or may not be present depending on the media version.
Modified procedures for extracting files for online and full iso images based on processor architecture.
Initial version