Update tutorial content

[codytodonnell]

Effort Summary:
The tutorial has not been updated recently to reflect changes in the underlying strudel-kit code and structure.

• Clarify that the tutorial is frontend focused
• Fix links to other places in the documentation (should point to https:/strudel.science/strudel-kit/storybook)
• Fix degit commands to reflect new repo structure
• Remove the "Remove Unused Task Flows" section
• Ensure all images are also migrated over and showing up in the tutorial
• Make a note in the "Add a Data Source" section about connecting to the backend in the future