feat: align en/es sites and recover spatial coverage

[rdahis]

Summary

Makes the English (data-basis.org) and Spanish (basedelosdatos.org) sites consistent by removing Portuguese/Brazil-specific elements, and restores the previously-hidden spatial coverage feature.

• Consulting banner — the dataset-page ServiceHighlightABTest now renders only on basedosdados.org, gated on NEXT_PUBLIC_DOMAIN via new getDomain()/isBasedosdadosDomain() helpers (build-time domain, so it's correct under Docker where the browser hostname is localhost).
• Generated query alias — the backend hardcodes the table alias as dados; localizeQueryTableAlias() rewrites it per locale (pt→dados, en→data, es→datos) across the SQL/Python/R snippets. Word-boundary replace leaves the basedosdados.<dataset>.<table> project path untouched.
• Spatial coverage (recovered, gated to non-pt):
  • dataset page shows it side-by-side with temporal coverage (getDataset now requests spatialCoverageName{Locale});
  • search result cards show it;
  • search left-column filter box, placed above Organization, backed by the /search spatial_coverages aggregation; hidden on pt.
• Homepage — drops Brazil-specific phrasing in en/es ("largest public data platform in Brazil" → "a large public data platform"; "socioeconomic data from Brazil"; the IBGE/Brazilian-municipalities example generalized). Testimonials left intact.

Depends on the backend PR (basedosdados/backend#TBD) for the spatial_coverages search aggregation that populates the filter box.

Test plan

• Verified locally (npm dev) against the production backend and a local Docker backend:
  • banner hidden on data-basis.org, shown on basedosdados.org;
  • generated query alias = data (en) / datos (es) / dados (pt);
  • dataset page + cards show spatial coverage on en/es, hidden on pt;
  • search filter box populates (International, Brazil, US, …), reorders above Organization, and is hidden on pt;
  • homepage copy free of Brazil mentions in en/es.
• next build passes (1292 pages, 0 errors).

🤖 Generated with Claude Code

[rdahis]

Backend dependency (spatial_coverages aggregation + world-filter fix): basedosdados/backend#1038

[rdahis]

@AldemirLucas não entendi se é para apontar para staging, para main, ou para as duas. Parece que vocês não estão mais seguindo o fluxo development -> staging -> main né.

O backend de staging já tá certo. Estou esperando subir para main também em basedosdados/backend#1039.

[rdahis]

Also opened against main: see the main-targeted PR for the same changeset.