fix(curriculum): refactor decimal to binary converter to check for positive numbers only

[Supravisor]

Checklist:

• I have read and followed the contribution guidelines.
• I have read and followed the how to open a pull request guide.
• My pull request targets the main branch of freeCodeCamp.
• I have tested these changes either locally on my machine, or GitPod.

Closes #54651

Step 1 text updated to show project will only covert positive numbers.
#54651 (comment) @jdwilkin4

But IMO, I think we should just add a note in the beginning for step 1 that this project will build out a binary converter for positive numbers.

#54651 (comment) @scissorsneedfoodtoo

Like Jessica mentioned, we could adjust the text in step 1 to emphasize that this project will only convert positive numbers into binary.

Updated instructions for step 12

Hint message for step 12 second condition

Hint message for step 12 third condition

Step 12 success message

Updated instructions for step 13

Hint message for step 13 - alert without text

Step 13 success message

Step 78 instructions

Hint message for step 78 - second condition

Hint message for step 78 - third condition

[JoyShaheb]

good so far! dropped some reviews and feedbacks

[jdwilkin4]

This PR was just merged in which addresses the same issue
#54708

As result, we are going to close your PR