fix: skip trailing padding in HII database parsing

[HarishCoder-Linux]

Add a guard in get_package_lists() to detect and skip trailing padding bytes (e.g., 0x00 or 0xFF) in the HII database blob. This prevents crashes caused by attempting to parse padding as a valid package list, which resulted in subtraction overflows.

Also ensures graceful exit if the remaining data is too short to form a valid package list header.