Get "Cómo te veo", the honest portrait built from the user's behaviour

Returns the stored portrait without calling the model. portrait is null until the first refresh. stale is true when there is no portrait or new data arrived after it was generated. nextRefreshAt is when POST /me/portrait/refresh will be accepted again (null: now). Portrait shape: { summary, style: { traits[], examples[] }, strengths: Evidence[], watchOuts: (Evidence & { severity: low|medium|high, pattern? })[], byFamily: { family, note }[], dataBasis: { contacts, messages, choices, edits } }, Evidence = { title, detail, contacts: { id, name }[] }.