Is there a way to include an option to save without submitting?

I am trying to create a form for a contract agreement. If the contract is a weekly contract, then the form must be saved and then edited upon completion of work to include an approval indicating that work was completed. I know I can set up a conditional email to be enable respondents to edit their response to include an approval after the initial submission, but then I have two pdfs in my Google Drive integrated folder that are created for the same contract, which is not ideal. I would prefer that the form not be submitted until it is approved.

You could use the save and continue feature if your form is a multi-page form:

https://www.jotform.com/help/97-How-to-Save-Forms-and-Continue-Later

But this feature is much less robust than using the edit submission link in emails.  It is prone to losing data if the session is cleared and requires using two forms instead of one.

The best option is indeed to use the edit submission link in an email autoresponder if you can live with the extra PDF generated in Drive.