{"changes":[{"id":"001-rename-postcode-to-zip-code","category":"rename-field","severity":"breaking","versionBump":"major","description":"Rename request body field \"postcode\" → \"zip_code\" on POST /api/quote. Existing callers sending \"postcode\" will fail body validation.","applied":false},{"id":"002-require-driver-age","category":"add-required-field","severity":"breaking","versionBump":"major","description":"driver_age becomes required on POST /api/quote (was optional). Callers omitting it will fail body validation.","applied":false},{"id":"003-vehicle-year-to-string","category":"change-field-type","severity":"breaking","versionBump":"major","description":"Change vehicle_year from integer to string (4-digit pattern) on POST /api/quote. Existing callers sending an int will fail body validation.","applied":false}]}