Record performance audit completion

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implement the performance audit revisions
 
-Status: Planned. Audience: a Luna coding agent implementing one stage at a time,
+Status: Complete. Audience: a Luna coding agent implementing one stage at a time,
 in numerical order. The [performance audit roadmap](performance-audit.md) owns
 the target and rationale. This plan replaces the completed ReleaseKit plan,
 which remains available in Git history at `0c77dee`.
@@ -435,7 +435,7 @@ Roadmap candidate 8. Owners: engine `resolution.go` and `load_metadata.go`.
 Validate: `go test ./internal/engine -run 'Resolution|Provenance|Overlay|Override|Inheritance|History'`
 and the everyday check. Small lists and outputs preserve existing semantics.
 
-## Stage 18: Review the completed result and record outcomes
+## Stage 18: Review the completed result and record outcomes — Complete
 
 1. Review the diff from baseline. Map all nine candidates to selected implemented
    changes and expressly deferred portions. Remove dead helpers/imports/state;
@@ -465,3 +465,31 @@ No public performance guarantee is created.
 None required for the selected scope. Algorithm, ownership, relation, ordering,
 and scope choices above are resolved. Expressly deferred experiments require
 separate design/evidence and do not block this sequence.
+
+### Final evidence and outcomes
+
+- Reviewed planning baseline `0c77deed05417edb32f42c7bf24df2fdc2581a25`,
+  production baseline `48619de024d794cf41e90b171b7fcbe609dcd437`, and the
+  complete implementation diff through `799ebab5a6f15e8252474b8cb7ea164ef503f390`.
+  The selected changes map to the audit candidates as follows: candidate 1 in
+  Stage 2; candidate 2 in Stages 4–5; candidate 3 in Stages 6–8; candidate 4
+  in Stage 12; candidate 5 in Stage 9; candidate 6 in Stages 10–11; candidate 7
+  in Stages 13–15; candidate 8 in Stages 16–17; and candidate 9 in Stage 3.
+- `GOTOOLCHAIN=local go version` reports `go1.26.8 linux/amd64`.
+  `go test ./internal/engine -run 'Resolution|Provenance|Overlay|Override|Inheritance|History'`,
+  `./scripts/check.sh`, and `go test -race ./...` passed. The development check
+  includes formatting, whitespace, all-package tests, vet, and build. No
+  environmental limitations were encountered.
+- The selected algorithms replace repeated pairwise/list scans or repeated
+  formatting with token comparisons, local prefix indexes, ordered membership
+  maps, direct visitors, and a worklist. Operation-local indexes and propagation
+  state are discarded after use. Inspection retains immutable node-to-mapping
+  position lookups and prepared replay descriptors for repeated read-only
+  queries; this trades additional retained index storage for reuse. Per-record
+  reason/dependency sets and materialized-step keys likewise use memory in
+  proportion to retained unique values while preserving ordered output slices.
+- Whole-tree explanation replay, public metadata-copy ownership redesign, global
+  schema caching, and complex contributor-trace membership indexing remain
+  deferred. Existing cloning and linked traces remain. No benchmark campaign
+  was run; expected work reductions are algorithmic, not measured runtime
+  claims, and no public performance guarantee is added.