refactor: remove dead utils/bench.rs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

meson.build

@@ -22,7 +22,7 @@ resources = gnome.compile_resources(
 
 cargo_target = custom_target(
   'ahfail-cargo-build',
-  input: ['src/lib.rs', 'Cargo.toml'],
+  input: ['crates/ahfail-gtklock/src/lib.rs', 'Cargo.toml'],
   output: ['libahfail_module.a'],
   command: [
     'sh', '-c', 'cargo build --release -p ahfail-gtklock --target-dir "@OUTDIR@/target" && cp "@OUTDIR@/target/release/libahfail_module.a" "@OUTPUT@"'