fix(whatsapp): handle partial Brazil phone numbers

app/services/whatsapp/phone_normalizers/brazil_phone_normalizer.rb

@@ -14,7 +14,7 @@ class Whatsapp::PhoneNormalizers::BrazilPhoneNormalizer < Whatsapp::PhoneNormali
     return waid unless handles_country?(waid)
 
     ddd = waid[COUNTRY_CODE_LENGTH, DDD_LENGTH]
-    number = waid[COUNTRY_CODE_LENGTH + DDD_LENGTH, waid.length - (COUNTRY_CODE_LENGTH + DDD_LENGTH)]
+    number = waid[(COUNTRY_CODE_LENGTH + DDD_LENGTH)..].to_s
     return waid unless number.match?(LEGACY_MOBILE_NUMBER_PATTERN)
 
     "55#{ddd}9#{number}"

app/services/whatsapp/phone_number_normalization_service.rb

@@ -29,15 +29,6 @@ class Whatsapp::PhoneNumberNormalizationService
     existing_contact_inbox&.source_id || raw_number
   end
 
-  # @param clean_number [String] Phone number in clean cloud format, e.g. "5541988887777"
-  # @return [String] Country-normalized number, or the original when no normalizer applies
-  def normalize_number(clean_number)
-    normalizer = find_normalizer_for_country(clean_number)
-    return clean_number unless normalizer
-
-    normalizer.normalize(clean_number)
-  end
-
   # Keep the provider value first so exact contact matches always win. Each
   # country normalizer explicitly opts into contact-safe alternatives; source-id
   # normalization alone is not enough because the alternate may be another

spec/services/whatsapp/phone_normalizers/brazil_phone_normalizer_spec.rb

@@ -0,0 +1,9 @@
+require 'rails_helper'
+
+describe Whatsapp::PhoneNormalizers::BrazilPhoneNormalizer do
+  describe '#contact_candidates' do
+    it 'preserves a partial Brazil number without raising' do
+      expect(described_class.new.contact_candidates('55')).to eq(['55'])
+    end
+  end
+end