Adds Team CRUD on /api/v2 mirroring the labels reference resource:
list, read, create, update, delete under /teams[/{id}].
- The list op exposes an include_public query param bound onto the
model so Team.ReadAll can surface public teams (gated by the instance
public-teams setting).
- Read ops emit an ETag and honor If-None-Match (304).
- Model fields gain doc: tags; server-controlled fields are marked
readOnly:true.
- Self-registers via init()/AddRouteRegistrar; no routes.go change.
- New webtest TestHumaTeam (named to avoid clashing with the v1 model
TestTeam) covers list/read/create/update/delete plus negatives
(non-member 403, nonexistent 403/404) and ETag/304.
kolaente