[tutorial] added misc UX improvements

[khannanov-nil]

Short Summary

This diff adds several UX improvements to interactive tutorials.

What Changes Were Made

• Added comments suggesting where exactly developers should add their code to tutorials.
• When a tutorial check fails and there is a fail receipt, the logs display the transaction hash for debugging.
• Completed solutions are cached and displayed when a developer accesses a completed tutorial.
• The text for most errors has been made clearer.

Related Issue

Addresses #703 .

Checklist

Please mark each item with an x inside the brackets (e.g., [x]) once completed.

• I have read and followed the Contributing Guide
• I have tested the changes locally
• I have added relevant tests (if applicable)
• I have updated documentation/comments (if applicable)

[KlonD90]

lgtm (but .on more readable notation than target)