bug: queue player counts, friend button state, highlight self filter, name change notifications

[lukepolo]

Web half of the fork-triage bug fixes. The queue count needs 5stackgg/api#409 to ship with it; the rest stand alone.

• Queue count: the api sent one entry per queued lobby and the badge counted lobbies, so a queued trio read as "1 in queue". It now counts players, with multi-region lobbies still counted once. Counting lives in a tested helper.
• Friend button: isFriend matched any my_friends row, including a still-pending one, so the hero showed the green "Friend" badge right after you sent a request — and again when someone sent you one. It now goes through useFriendActions: add / requested / accept / friend, with the in-flight state the rest of the app already uses.
• Highlights: the player filter never offered you, so you could not filter to your own clips.
• Name change notifications: the body was the one type rendered as plain text, so an api-escaped name showed up as '. It renders like every other type now (sanitized), and the notification shows the player card, so it links to the profile.
• Teams: the owner no longer sees Leave. Nothing reassigned ownership, so leaving left the team owned by a non-member that only a site admin could manage. The database enforces the same rule in the api PR.

Tests: 98.