Carry the municipality range on a not-found CEPHEADv0.2.0main

A CEP that fails a lookup is rarely a random number. It is usually
someone who knows the city and guessed the digits, and the classic guess
is the -000 that 957 municipalities never received. The API now answers
those 404s with a faixa naming the municipality whose band the number
falls into, so a caller can ask "did you mean somewhere in Areal/RJ?"
instead of returning a bare "not found".

Cep_not_found becomes an inline record so the context rides along with
the message, matching how Rate_limited and Server_error already carry
theirs. It is still a 404: faixa is context on the failure and never
promotes it to an address, and its bounds are the smallest and largest
CEP that actually exist there — sparse across the interval, which is
what the ceps count is for — not the bounds the Correios publish.

Parsing is deliberately lenient. A missing, null, malformed or
municipality-less faixa yields None rather than an error: a 404 is a
clean answer, and no shape of this field should turn it into an
Invalid_response.

1 files changed, 1 insertions, 1 deletions

diff --git a/dune-project b/dune-project
index 3e7fa0f..cf8de14 100644
--- a/dune-project
+++ b/dune-project
@@ -2,7 +2,7 @@
 
 (name cepis)
 
-(version 0.1.0)
+(version 0.2.0)
 
 (generate_opam_files true)