edge-bench-rs: libdeflate for chunks, memchr for lines and tabs

libdeflate inflates a chunk whole, in half the time of zlib-rs (1.09 ->
0.51 s per boneless range); memchr finds line ends and tabs with SIMD.
The per-article timers are gone. Boneless 2026 ~700k headers/s, ath 2013
~920k; all three captures still identical to the TypeScript.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tools/edge-bench-rs/src/indexer.rs

@@ -195,9 +195,7 @@ impl Scanner {
         let file = match self.files.get(self.key.as_str()) {
             Some(f) => f.clone(),
             None => {
-                let t = std::time::Instant::now();
                 let f = describe(subject, name_end, &counter, from, xref, group).map(Rc::new);
-                unsafe { PROF[0] += t.elapsed().as_nanos() as u64; PROF[1] += 1; }
                 self.files.insert(self.key.clone(), f.clone());
                 f
             }
@@ -212,7 +210,7 @@ impl Scanner {
             message_id: id.to_string(),
             bytes: js::parse_int(bytes).unwrap_or(0),
             article,
-            posted_at: { let t = std::time::Instant::now(); let d = js::parse_date(date); unsafe { PROF[2] += t.elapsed().as_nanos() as u64; } d },
+            posted_at: js::parse_date(date),
             file,
         })
     }
@@ -244,20 +242,18 @@ fn scan_overview_text(text: &str, mut line: impl FnMut(Option<i64>, &str, &str,
     let b = text.as_bytes();
     let mut start = 0;
     while start < b.len() {
-        let end = memchr(b'\n', &b[start..]).map(|i| i + start).unwrap_or(b.len());
+        let end = memchr::memchr(b'\n', &b[start..]).map(|i| i + start).unwrap_or(b.len());
         let stop = if end > start && b[end - 1] == b'\r' { end - 1 } else { end };
         if stop > start {
             let l = &text[start..stop];
             let lb = l.as_bytes();
             let mut tabs = [usize::MAX; 9];
             let mut n = 0;
-            for (i, &c) in lb.iter().enumerate() {
-                if c == b'\t' {
-                    tabs[n] = i;
-                    n += 1;
-                    if n == 9 {
-                        break;
-                    }
+            for i in memchr::memchr_iter(b'\t', lb) {
+                tabs[n] = i;
+                n += 1;
+                if n == 9 {
+                    break;
                 }
             }
             if n >= 5 {
@@ -279,10 +275,6 @@ fn scan_overview_text(text: &str, mut line: impl FnMut(Option<i64>, &str, &str,
     }
 }
 
-fn memchr(needle: u8, haystack: &[u8]) -> Option<usize> {
-    haystack.iter().position(|&c| c == needle)
-}
-
 struct OpenFile {
     parts: Vec<Seg>,
     seen: FxHashSet<u32>,