Allow sites to have donate links

User story

As a PlaceCal organiser, I want to be able to link my partnerships' fundraising site prominantly in order that we can make our efforts to organise the community sustainable

Acceptance criteria

• [ ] Simple MVP: allow sites to list an external donate link in the menu bar
• [ ] Ideally we need PlaceCal to have a way to track how much

Implementation notes & questions

Ideally this would be something we control and take a percentage of but this would be significantly more complicated. For now we prob just need an MOU with partnerships that if they make money they either start paying us monthly subs or a percentage.

Implementation plan

To be written by the developer

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