Final completeness by time window: ranges keep their posting span, release_final() over blocks of done ranges

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

lib/edge/range_indexer.ts

@@ -77,6 +77,13 @@ export interface EdgeBatch {
   /** First article number not covered yet. */
   next: number
   headers: number
+  /**
+   * The batch's posting times without its earliest and latest 1% (ms; null without a dated article): the range's
+   * time span is their min and max (headers dated years off don't stretch it). The settler's final completeness
+   * reads it (LOG.md 2026-10-16 (67)).
+   */
+  postedLow: number | null
+  postedHigh: number | null
   releases: ReleaseChunk[]
   samples: DroppedChunk[]
   candidates: ProbeCandidate[]
@@ -115,6 +122,8 @@ export class RangeIndexer {
   private aggregator = new FileAggregator<EdgeSegment>(UPLOAD_GAP_MS)
   private scanner = new SegmentScanner()
   private segments: EdgeSegment[] = []
+  /** Posting times of this batch's segments (postedSpan at take). */
+  private dates: number[] = []
   private rules: RuleSet
   private batch: EdgeBatch
   private counts = new Map<string, RuleCount>()
@@ -155,8 +164,10 @@ export class RangeIndexer {
       return
     }
     const segment = this.scanner.segment(articleNumber, subject, from, date, messageId, bytes, xref, group)
-    if (segment) this.segments.push(segment)
-    else this.count('obfuscated', '', 1, 0)
+    if (segment) {
+      this.segments.push(segment)
+      if (Number.isFinite(segment.postedAt)) this.dates.push(segment.postedAt)
+    } else this.count('obfuscated', '', 1, 0)
   }
 
   private endChunk(next: number) {
@@ -180,6 +191,8 @@ export class RangeIndexer {
     const out = this.batch
     out.counts = [...this.counts.values()]
     this.counts.clear()
+    ;[out.postedLow, out.postedHigh] = postedSpan(this.dates)
+    this.dates = []
     this.batch = this.empty(out.next)
     return out
   }
@@ -290,10 +303,18 @@ export class RangeIndexer {
   }
 
   private empty(from: number): EdgeBatch {
-    return { from, next: from, headers: 0, releases: [], samples: [], candidates: [], counts: [], fragments: [] }
+    return { from, next: from, headers: 0, postedLow: null, postedHigh: null, releases: [], samples: [], candidates: [], counts: [], fragments: [] }
   }
 }
 
+/** Posting times without the earliest and latest 1% (floor(n / 100) at each end); nulls without any. */
+export function postedSpan(dates: number[]): [number | null, number | null] {
+  if (dates.length === 0) return [null, null]
+  const sorted = Float64Array.from(dates).sort()
+  const k = Math.floor(sorted.length / 100)
+  return [sorted[k], sorted[sorted.length - 1 - k]]
+}
+
 /** The release key; a file without a recognisable release becomes a release of its own. */
 export function releaseKeyOf(s: EdgeSegment): string {
   return s.file.release?.key ?? hash('sha1', `file\n${s.fileKey}`)