Add partstat to CalendarEvent

[joelhawksley]

Context

When working with calendar events, it can be useful to filter by response status. For example, one might want to hide events that have been declined.

Proposal

Add a partstat field to CalendarEvent per rfc5545.

Impact

As this change adds a field, I do not believe it will cause any breakages.

Proof of concept

home-assistant/core#125708

[allenporter]

PARTSTAT is not a top level rfc5545 component property. It is a property parameter of another property, Attendee. As a result, this feels like it should be #1099

Would be good to be specific about which calendar integrations you plan to update to use this and how it will work.

[joelhawksley]

Ultimately, I think either way is fine with me. I'd be happy to help implement whichever path makes the most sense to y'all. How can I help move this forward?

[allenporter]

As i mentioned above: I think it would be way simpler to just make a breaking change to the behavior of google calendar since it probably matches what users want. As a codeowner for google calendar integration, i'd support this.

[joelhawksley]

Ok, would you be 👍🏻 to me trying to write a PR to core to do so?

[allenporter]

Yes, happy for you to send a PR.