feature/022-disable-add-to-dashboard-button

Changing this to WIP. It's in an odd state.

Purpose
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Prevent multiple clicks from submitting requests before the first request has finished.

Changes
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Disable the link upon clicking the button, and re-enable only on successful completion of the change.

Modify error messages to be more descriptive.

Add explicit Raven logging for errors.

Side effects
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If the request fails, inform the user that they need to reload to re-enable the functionality and keep the button disabled. Re-enable when the button