Lazy stages

• Lazy stage constructors added;
• Iterator constructor implemented as a method on Gen[T]

Iterator type renamed.

pump.Seq renamed to pump.It, to make it distinct from iter.Seq.

API updates

• Iterator type renamed to pump.Seq
• Added constructors from iter.Seq and slice.

Bug fix release

Fixed bug in test code, plus README update.

Updated with for-range iterator type.

This release adds for-range iterator type and sets the minimum Go version to 1.23.

First release

First release.