edge-bench --group: a range after a gap starts its batch at the range

a.b.storage's stored 2016 ranges are not contiguous (its 2016 window lies in two
article regions); the batch after a gap kept the previous range's end as its
start and the harness found no leased range for it.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

edge/src/indexer.rs

@@ -937,6 +937,15 @@ impl RangeIndexer {
         self.batch.next = self.end + 1;
     }
 
+    /// The next range of a group starts after a gap (edge-bench --group, the corpus holding some ranges only): a fresh
+    /// batch starts there, not at the previous range's end; the window carries on. Nothing when the batch has anything.
+    pub fn skip_to(&mut self, article: i64) {
+        if self.batch.headers == 0 && self.batch.releases.is_empty() && self.batch.candidates.is_empty() && self.batch.from < article {
+            self.batch.from = article;
+            self.batch.next = article;
+        }
+    }
+
     /// Files in the releases finished since the last take (RangeIndexer.pending).
     pub fn pending(&self) -> usize {
         self.pending_files

edge/src/main.rs

@@ -292,6 +292,10 @@ fn main() {
     for (ri, range) in ranges.iter().enumerate() {
         let range_wall = Instant::now();
         let headers_before = out.0;
+        // After a gap between stored ranges the batch starts at this range (every range ends with a batch taken).
+        if ri > 0 {
+            indexer.skip_to(range.start);
+        }
         let mut files: Vec<String> = std::fs::read_dir(&range.dir).unwrap().map(|e| e.unwrap().file_name().into_string().unwrap()).filter(|f| f.ends_with(".gz")).collect();
         files.sort();
         for (i, file) in files.iter().enumerate() {