Revise sieve's exercise instructions

[tasxatzial]

Forum discussion

https://forum.exercism.org/t/updating-sieve-exercise-instructions/15703

Summary of the changes:

• Clarified that the starting numbers are "from 2 up to and including your given number".
• Removed explicit references to lists to avoid conflicts with track-specific terminology. Exercise no longer asks to create a list and return a list.
• Updated the note to clarify how the Sieve marks off multiples of each prime.
• Removed references to division and remainder operations from the note, as there are multiple ways to check for divisibility.
• Updated the example to show what happens at each step. I'll revert this change if there's any disagreement. If anyone has a better way to indicate the result of each step, please share it here.