Kernel: Update ErrorOr API and add path find to VFS

These two are done on the same commit since Changes to Shell were
annoying to make work with only one change

kernel/include/kernel/FS/VirtualFileSystem.h

@@ -14,6 +14,8 @@ namespace Kernel
 
 		virtual const BAN::RefCounted<Inode> root_inode() const override { return m_root_inode; }
 
+		BAN::ErrorOr<BAN::RefCounted<Inode>> from_absolute_path(BAN::StringView);
+
 	private:
 		VirtualFileSystem(BAN::RefCounted<Inode> root_inode)
 			: m_root_inode(root_inode)