style(bench): rustfmt the blob/pool/runtime bench examples

These example targets landed unformatted on main and fail the Rustfmt CI
check (`cargo fmt --all --check`); reformat them so this PR's checks pass.
No logic changes.

examples/bench_blob_prefetch.rs

@@ -47,13 +47,20 @@ use oxicloud::application::ports::blob_storage_ports::BlobStorageBackend;
 use oxicloud::infrastructure::services::local_blob_backend::LocalBlobBackend;
 
 fn env_or<T: std::str::FromStr>(key: &str, default: T) -> T {
-    env::var(key).ok().and_then(|v| v.parse().ok()).unwrap_or(default)
+    env::var(key)
+        .ok()
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(default)
 }
 
 fn env_list_usize(key: &str, default: &[usize]) -> Vec<usize> {
     env::var(key)
         .ok()
-        .map(|s| s.split(',').filter_map(|x| x.trim().parse().ok()).collect::<Vec<_>>())
+        .map(|s| {
+            s.split(',')
+                .filter_map(|x| x.trim().parse().ok())
+                .collect::<Vec<_>>()
+        })
         .filter(|v: &Vec<usize>| !v.is_empty())
         .unwrap_or_else(|| default.to_vec())
 }
@@ -130,7 +137,11 @@ async fn run_once(
     // Coarse token-bucket: only sleep once the accumulated owed time clears a
     // 2 ms floor, so the throttle models a rate-limited socket without drowning
     // the measurement in sub-ms timer noise.
-    let per_byte_secs = if throttle_bps > 0.0 { 1.0 / throttle_bps } else { 0.0 };
+    let per_byte_secs = if throttle_bps > 0.0 {
+        1.0 / throttle_bps
+    } else {
+        0.0
+    };
     let mut owed = Duration::ZERO;
 
     while let Some(item) = byte_stream.next().await {
@@ -196,15 +207,18 @@ async fn main() {
         "# production LocalBlobBackend.read_prefetch() = {}",
         backend.read_prefetch()
     );
-    println!("# reps/cell: {reps} (median MB/s reported)  cold-cache: {}", {
-        if !COLD_SUPPORTED {
-            "unsupported (non-Linux) → warm only"
-        } else if want_cold {
-            "yes (posix_fadvise DONTNEED, best-effort)"
-        } else {
-            "disabled (BENCH_COLD=0)"
+    println!(
+        "# reps/cell: {reps} (median MB/s reported)  cold-cache: {}",
+        {
+            if !COLD_SUPPORTED {
+                "unsupported (non-Linux) → warm only"
+            } else if want_cold {
+                "yes (posix_fadvise DONTNEED, best-effort)"
+            } else {
+                "disabled (BENCH_COLD=0)"
+            }
         }
-    });
+    );
     println!("# N=1 is current production ('antes'); higher N is the candidate ('después')");
     println!("############################################################\n");
     println!(

examples/bench_pool_concurrency.rs

@@ -29,7 +29,10 @@ use oxicloud::infrastructure::services::thumbnail_service::ThumbnailService;
 use tokio::sync::Semaphore;
 
 fn env_or<T: std::str::FromStr>(key: &str, default: T) -> T {
-    std::env::var(key).ok().and_then(|v| v.parse().ok()).unwrap_or(default)
+    std::env::var(key)
+        .ok()
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(default)
 }
 
 #[cfg(target_os = "linux")]
@@ -181,7 +184,9 @@ fn main() {
     );
     println!(
         "# available_parallelism = {}   effective_parallelism = {}  (= the 'after' permit count)",
-        std::thread::available_parallelism().map(|n| n.get()).unwrap_or(0),
+        std::thread::available_parallelism()
+            .map(|n| n.get())
+            .unwrap_or(0),
         eff
     );
     println!("# run under `taskset -c 0,1` to model a 2-core quota");
@@ -190,7 +195,10 @@ fn main() {
         "| {:>8} | {:>9} | {:>10} | {:>9} | {:>9} |",
         "permits", "renders", "renders/s", "p50 ms", "p99 ms"
     );
-    println!("|{:-<10}|{:-<11}|{:-<12}|{:-<11}|{:-<11}|", "", "", "", "", "");
+    println!(
+        "|{:-<10}|{:-<11}|{:-<12}|{:-<11}|{:-<11}|",
+        "", "", "", "", ""
+    );
 
     // Warm up (also triggers corpus generation / codec init).
     let _ = bench_k(&rt, img.clone(), 2, producers, 1);
@@ -206,7 +214,10 @@ fn main() {
 
     // ── Part B: peak RSS for K concurrent decodes (the real over-permit cost) ──
     println!("\n[B] Peak RSS with K concurrent decodes (one wave)\n");
-    println!("| {:>8} | {:>14} | {:>12} |", "permits", "peak RSS MiB", "vs effective");
+    println!(
+        "| {:>8} | {:>14} | {:>12} |",
+        "permits", "peak RSS MiB", "vs effective"
+    );
     println!("|{:-<10}|{:-<16}|{:-<14}|", "", "", "");
     let mut eff_rss: Option<u64> = None;
     for &k in &k_list {

examples/bench_tokio_runtime.rs

@@ -35,7 +35,10 @@ use std::time::{Duration, Instant};
 use oxicloud::common::runtime::{cgroup_cpu_quota, effective_parallelism, runtime_pool_sizes};
 
 fn env_or<T: std::str::FromStr>(key: &str, default: T) -> T {
-    env::var(key).ok().and_then(|v| v.parse().ok()).unwrap_or(default)
+    env::var(key)
+        .ok()
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(default)
 }
 
 #[cfg(target_os = "linux")]
@@ -204,9 +207,7 @@ fn main() {
 
     // ── Part A ──────────────────────────────────────────────────────────────
     println!("\n[A] Worker over-subscription under CPU contention");
-    println!(
-        "    workload: {concurrency} concurrent requests, {burn_kb} KiB BLAKE3 each, {secs}s"
-    );
+    println!("    workload: {concurrency} concurrent requests, {burn_kb} KiB BLAKE3 each, {secs}s");
     println!("    (run under `taskset -c 0,1` to model a 2-core quota)\n");
     println!(
         "| {:<26} | {:>8} | {:>10} | {:>8} | {:>8} |",
@@ -227,7 +228,13 @@ fn main() {
         before.2,
         before.3
     );
-    let after = bench_workers(workers_after, def_max_blocking, concurrency, secs, burn_bytes);
+    let after = bench_workers(
+        workers_after,
+        def_max_blocking,
+        concurrency,
+        secs,
+        burn_bytes,
+    );
     println!(
         "| {:<26} | {:>8.0} | {:>10} | {:>8} | {:>8} |",
         format!("after: {workers_after} workers"),
@@ -259,7 +266,8 @@ fn main() {
         "| {:<26} | {:>12} | {:>12} |",
         "before: 512 (tokio default)", peak_def, "—"
     );
-    let (peak_cap, _base_cap) = bench_blocking_rss(max_blocking_after, blocking_tasks, alloc_mb, hold_ms);
+    let (peak_cap, _base_cap) =
+        bench_blocking_rss(max_blocking_after, blocking_tasks, alloc_mb, hold_ms);
     let saved = peak_def as i64 - peak_cap as i64;
     println!(
         "| {:<26} | {:>12} | {:>12} |",