Can add a loan preparation without a quantity

[combs-a]

Describe the bug
You can empty out the Selected field when selecting preparations for a new loan and save it without a quantity. Furthermore, you can empty the quantity field on a existing loan and still save.

Unsure if the second behavior is intended (because you don't get a save blocker when having the field empty or 0 on an existing loan), but the first one definitely isn't. When creating a new loan, setting the value to 0 means that it shouldn't be selected. This is effectively the same case.

To Reproduce
Steps to reproduce the behavior:

1. Go to Interactions -> Loan
2. Choose either record set or catalog number
3. At the list of preparations, empty one of the Selected fields
4. See that even though it's empty, it's now checked
5. Click apply and see that it goes through
6. Add a loan number
7. Try to save, see that a save blocker pops up for a second
8. Click somewhere else on the form and see that the save blocker is cleared and you can now save

Expected behavior
Similar to negative numbers and numbers larger than the amount of preparations, this should not be allowed; preferably clicking Apply should block this.

Screenshots

badloan.mp4

Please fill out the following information manually:

• OS: Windows 10
• Browser: Firefox and Chrome
• Specify 7 Version: production (v7.9.11) and v7.9.6.2
• Database Name: sdnhm_herps_2_8_24
• Collection name: Herp-PC
• User Name: testuser
• URL: N/A