Squashed 'vendor/ruvector/' content from commit b64c2172

git-subtree-dir: vendor/ruvector
git-subtree-split: b64c21726f2bb37286d9ee36a7869fef60cc6900

crates/prime-radiant/benches/attention_bench.rs

@@ -0,0 +1,15 @@
+//! Attention-weighted coherence benchmarks
+
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+
+fn attention_benchmark(c: &mut Criterion) {
+    let mut group = c.benchmark_group("attention");
+
+    // Placeholder benchmark - requires attention feature
+    group.bench_function("placeholder", |b| b.iter(|| black_box(42)));
+
+    group.finish();
+}
+
+criterion_group!(benches, attention_benchmark);
+criterion_main!(benches);