Function application_fields 

pub fn application_fields<'a>(
    name: &'a str,
    package_id: &'a str,
    category: Option<&'a str>,
    description: Option<&'a str>,
) -> [(&'a str, FieldWeight); 5]

An app’s searchable fields. The package id in full, or its last segment, identifies exactly one app and weighs as its name — hex-editor typed for so.tilo.hex-editor is the app’s identity and must outrank an incidental substring. Category ranks below the id because it’s a bucket, not an identity.