refactor: remove unused score.rs module

Per review feedback - the Score type wasn't actually used anywhere
in the codebase, so remove it rather than keeping dead code with
allow(dead_code) attributes.

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Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: sanity

crates/core/src/ring/mod.rs

@@ -37,13 +37,9 @@ mod connection;
 mod live_tx;
 mod location;
 mod peer_key_location;
-mod score;
 mod seeding;
 mod seeding_cache;
 
-#[allow(unused_imports)] // Score will be used as refactoring progresses
-pub use score::Score;
-
 pub use self::live_tx::LiveTransactionTracker;
 pub use connection::Connection;
 pub use location::{Distance, Location};