CR46: allow loading personas where address doesn't geocode (parks/hospitals/mataderos)

CR46: 'no podemos cargar personas en parques u hospitales' — loading a person fails when the address doesn't geocode to a known CABA street (repro: 'Mataderos' → 'No se pudo geolocodificar la direccion ingresada'). Root cause: intake requires a streets-table match / successful geocode. Fix intent: let a volunteer STILL save the person when the address can't be geocoded — e.g. manual map-pin / lat-lng capture, or a free-text location with a fallback marker — so parks/hospitals/plazas/informal locations aren't blocked. Assess-first: trace the geocode+validation path in the nueva-persona flow, then PROPOSE the fallback UX + data shape before coding (does cases store lat/lng directly? is address required NOT NULL?). Coordinate with db-ayudarg-cc if a column/nullability change is needed. Mobile-first. Report plan before push.