dynamic panel editor enhancements

[RyanCoulsonCA]

Related Item(s)

#342

Changes

• Disable the "Add New" button if the ID isn't filled out when adding a new panel.
• Fix issue with duplicate ID string being cut off.
• Added an additional confirmation step before deleting subpanels.

Testing

Steps:

1. Open the demo page and load a product.
2. Create a dynamic panel and add some subpanels.
3. Try to add a new subpanel with no name and ensure that you can't click Add new.
4. Try to add a new subpanel with the same name as another subpanel. Ensure the error message pops up and it's not cut off.
5. Try to remove a subpanel and ensure the additional confirmation message pops before it is removed.

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This change is 

[github-actions]

Your demo site is ready! 🚀 Visit it here: https://ramp4-pcar4.github.io/storylines-editor/fix-342

[yileifeng]

Found two issues when testing:

1. After creating a new dynamic panel, the first subpanel cannot be deleted (no action when removing).
2. When accessing an existing dynamic panel on the 0000 product (second slide), the config seems to be breaking the schema validator (resulting in other issues such as not being able to delete the slide). This also seems to happen when creating a new empty dynamic panel:
   

Reviewable status: 0 of 2 files reviewed, all discussions resolved

[RyanCoulsonCA]

I've fixed the issue with deleting the first subpanel, and the issue with the new dynamic panel showing an error in the advanced editor. That version of the 0000 product seems to be quite outdated (notice that the slideshow entry still has the images property instead of items), which is why that's erroring.

Reviewable status: 0 of 3 files reviewed, all discussions resolved

[yileifeng]

Reviewed 3 of 3 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @RyanCoulsonCA)

[dnlnashed]

Reviewed 3 of 3 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @RyanCoulsonCA)