Find a street address

The forward counterpart to address_at, and finer than geocode, which
answers at city/neighborhood granularity and never at a doorway. The
first comma splits the street from the city; a bare integer at either end
of the street part is the house number ("1600 Amphitheatre Parkway",
"Hauptstraße 5"). Pass `number`/`street`/`city` instead if you already
have the parts. Unit/apartment numbers are not parsed.

A street part written as a crossing with no house number — "5th Ave &
42nd St, New York, NY", also "A and B", "A at B", "A / B", "A @ B" — is
routed to geocode_intersection with the same city and returns that tool's
answer ({"results": [{lat, lon, streets}], "anchor", "note"}) plus
"delegated_to": "geocode_intersection". "and"/"at" only split when both
halves look like streets (a street-type word or an ordinal each), so
"Rock and Roll Hall of Fame Blvd, Cleveland" is still one street.

The city is resolved first and its boundary bounds the search, so a city
that resolves to no boundary — or to something far larger than a city,
like a state — returns an empty list plus a note rather than a scan. If a
same-named runner-up in the same country supplies the boundary instead,
the note names it — the answer is never silently about a different city,
and never about one in another country. Check `anchor` (name, country,
admin_context) to see which one it was. Street names match in either
spelling (Parkway/Pkwy, West/W, NW/Northwest).

Returns {"results": [{number, street, unit, postcode, country,
distance_m, lat, lon}, ...], "anchor": {name, id, country,
admin_context}, "match": "exact"|"nearest_number"|"street"},
deduplicated to distinct number+street+postcode and nearest the city's
own point first. More matches than `limit` adds "truncated",
"distinct_in_range" and a note. `match` is absent only when no street
was scanned at all (no street name, no city, or an unresolved anchor).

A requested number with no address point is never interpolated: when the
street has other numbered points, `results` holds the real nearest known
numbers bracketing the miss instead (`match: "nearest_number"`, each row
its own genuine coordinates, plus a note naming the miss and neighbors)
— never a synthesized coordinate for the missing number. No usable
numbers on the street falls to `match: "street"`, today's empty-plus-note.

Coverage is alpha: 39 countries, no UK, Ireland, India or China. An empty
list is a valid answer and always carries a note saying whether the
country is uncovered or the street simply wasn't found.