feat(pipeline): feed the current source page into the extraction prompt (#106) (#132)

Co-authored-by: Mathias <mthbqv@gmail.com>

ingestion/internal/wiki/merge.go

@@ -64,23 +64,50 @@ func MergeReport(a, b Page) (Page, []string) {
 	fmB, _, secsB := parseSections(b.Content)
 
 	var conflicts []string
-	idx := make(map[string]int, len(secsA))
+
+	// Sections in secsA sharing a normalized heading (pre-existing corpus
+	// drift — "## Notes" and "## NOTES" both already on disk, the exact
+	// pattern this normalization exists to catch going forward, found in
+	// review of PR #130/#132) are matched to b's occurrences of that same
+	// heading POSITIONALLY: b's 1st occurrence of the key pairs with a's
+	// 1st, b's 2nd with a's 2nd, and so on. A single "last write wins" (or
+	// even "first write wins") map from key to one index would instead
+	// route every one of b's occurrences to the SAME on-disk section —
+	// which either freezes every duplicate but one (never receiving
+	// updates again) or, worse, compares mismatched pairs and reports a
+	// disagreement between two sections that were never supposed to be
+	// compared, false-positiving on the plain self-merge case a revision
+	// pass produces when the model echoes a page back unchanged (found in
+	// review of PR #132).
+	byKey := make(map[string][]int, len(secsA))
 	for i, s := range secsA {
-		idx[s.heading] = i
+		key := normalizeHeading(s.heading)
+		byKey[key] = append(byKey[key], i)
 	}
+	cursor := make(map[string]int, len(byKey))
 
 	for _, sB := range secsB {
-		i, exists := idx[sB.heading]
-		if !exists {
-			idx[sB.heading] = len(secsA)
+		key := normalizeHeading(sB.heading)
+		indices := byKey[key]
+		pos := cursor[key]
+		cursor[key] = pos + 1
+
+		if pos >= len(indices) {
+			// b has more occurrences of this heading than a does (including
+			// the case where a has none at all) — the extra is new content,
+			// appended as its own section and registered so a THIRD
+			// occurrence of the same heading in b pairs with this one
+			// rather than appending yet another duplicate.
+			byKey[key] = append(byKey[key], len(secsA))
 			secsA = append(secsA, sB)
 			continue
 		}
+		i := indices[pos]
 		sA := secsA[i]
 		switch {
-		case bulletSections[sB.heading]:
+		case bulletSectionsNorm[key]:
 			secsA[i].content = mergeBullets(sA.content, sB.content)
-		case appendSections[sB.heading]:
+		case appendSectionsNorm[key]:
 			secsA[i].content = appendNew(sA.content, sB.content)
 		default:
 			// a wins — but say that b disagreed, rather than dropping it mute.
@@ -93,6 +120,34 @@ func MergeReport(a, b Page) (Page, []string) {
 	return Page{Path: a.Path, Content: rebuildContent(refreshOwned(fmA, fmB), preambleA, secsA)}, conflicts
 }
 
+// normalizeHeading returns the key Merge uses to decide "is this the same
+// section" — trimmed and case-folded, so "Key Claims" and "Key claims" match
+// (hyperguild#106: heading casing drift must not fork a section). It is used
+// only for that comparison; the on-disk section's original heading text
+// (secsA[i].heading, untouched here) is what actually gets written out, so a
+// human's heading casing is never silently rewritten by a merge.
+func normalizeHeading(h string) string {
+	return strings.ToLower(strings.TrimSpace(h))
+}
+
+// bulletSectionsNorm and appendSectionsNorm are bulletSections/appendSections
+// keyed by normalizeHeading instead of exact text, so a section's merge
+// strategy (union bullets, append) is chosen by the same normalized identity
+// Merge uses to match it — otherwise a heading that matched an on-disk
+// section (case-insensitively) could still fail the exact-string strategy
+// lookup and silently fall through to "keep a's version," dropping b's
+// content instead of unioning or appending it.
+var bulletSectionsNorm = normalizeSet(bulletSections)
+var appendSectionsNorm = normalizeSet(appendSections)
+
+func normalizeSet(names map[string]bool) map[string]bool {
+	out := make(map[string]bool, len(names))
+	for k := range names {
+		out[normalizeHeading(k)] = true
+	}
+	return out
+}
+
 // generatorOwned names the frontmatter fields the ingest pipeline may refresh
 // on a page it is revising. Everything else on disk wins.
 //