Avoid duplicate intermediate source history

docs/roadmap/remediation.md

@@ -123,7 +123,13 @@ checks effective and historical redaction.
 
 ## 2. Intermediate Source Definitions Are Duplicated In Metadata History
 
-Priority: P2. Status: open.
+Priority: P2. Status: complete.
+
+Completion: displaced definitions are omitted only when a preceding operation
+already introduced that concrete path with the same represented origin.
+`TestTierHistoryRecordsEachContributionOnce` failed before the fix and passes
+for both differing and equal-valued tiers. The full ordinary suite and
+`git diff --check` passed, including the existing shape-change regressions.
 
 Relevant code: `observeSourceEvidence` in
 [history_source.go](../../internal/engine/history_source.go), lines 82–117;