Allow clients to get a list of the account's teams

[nickvergessen]

isMemberOfTeam to be passed with parsed user mentions (system messages, comments. autocomplete mentions)

Originally posted by @Antreesy in #12036

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Similar to the list of groups, clients, desktop and web would need this information to know if they should highlight a circle mention in primary.

[nickvergessen]

• lighter api to get circles circles#1863 was added and backported
• So we should be able to try the endpoint and use it, theres no capability, but it's basically meant to always be available on 29+ in the future. So just make sure you're falling back on a 404 to an empty list?

[Antreesy]

I didn't close it due to mobile clients, is it relevant?