Allow users to unsubscribe via "Manage Subscription" modal

[guillermo-escire]

References

Fixes #5922

Description

Allows users to unsubscribe from a Community or Collection directly from the "Manage Subscription" modal by submitting with all frequency checkboxes unchecked.

Instructions for Reviewers

List of changes in this PR:

• Modified isValid logic to also enable the Submit button when an existing subscription is present, even if all frequencies are unchecked (indicating intent to delete)
• Added delete logic in submit(): when a subscription exists but all frequencies are unchecked, it calls deleteSubscription() instead of update
• Removed the helper text that redirected users to the /subscriptions page to unsubscribe, since it is no longer necessary

How to test:

1. Log in as administrator
2. Navigate to any Community or Collection
3. Click ⋮ → Subscribe, select at least one frequency, click Submit
4. Open the same dialog again (now "Manage subscription")
5. Uncheck all frequency checkboxes
6. Verify the Submit button remains enabled
7. Click Submit — subscription should be deleted and a success notification appears

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[nathanmlf]

Hey @guillermo-escire! I've tested the feature and the modal works as expected. I've attached a video below demonstrating the behavior. Nice job! Although it works well on my end, it would be great to have another reviewer test it as well.

pr_6092.mp4

[lgeggleston]

✅ Tested this as well and agree the functionality works well! The subscriptions are updated or deleted as expected whether from the collection itself or the Subscriptions page. Had some tiny code suggestions, but ready to approve after that. Thanks for the fix!

[lgeggleston]

This comment could be updated to reflect the new logic (remove "at least one frequency is checked")

[guillermo-escire]

Hi @lgeggleston , done, updated the comment to reflect the new logic.

[lgeggleston]

Since this attribute is no longer being used, would suggest removing it

[guillermo-escire]

hi @lgeggleston , done, removed the unused attribute.