Macro rule_common_impl 

macro_rules! rule_common_impl {
    () => { ... };
}

Stamp out the three boilerplate Rule impl methods every rule kind ships: id, level, policy_url. Expects the impl’ing struct to have fields named id: String, level: Level, and policy_url: Option<String> (the universal shape every rule builder hands back).

Usage inside an impl Rule for SomeRule block:

impl Rule for FileExistsRule {
    alint_core::rule_common_impl!();

    fn evaluate(&self, ctx: &Context<'_>) -> Result<Vec<Violation>> { ... }
    // ... other trait methods specific to this rule
}

The macro only covers the three universal methods. fixer() / as_per_file() / evaluate() / requires_full_index() etc. stay explicit per-rule because they encode the rule’s actual behaviour, not boilerplate.