Record validation and rendering baselines

docs/roadmap/implementation.md

@@ -2,7 +2,8 @@
 
 Implement the remaining local work in the [performance roadmap](performance.md)
 in order. Each sequential stage is scoped for one Luna coding-agent prompt.
-All stages below are pending. Update their status and evidence as work lands.
+Stage 1 is complete; Stages 2–14 remain pending. Update status and evidence
+as each work unit lands.
 The completed inspection plan is preserved at
 `481e2d4:docs/roadmap/implementation.md` in Git history.
 
@@ -93,6 +94,11 @@ retention, or maintenance trade-off; the original percentages are not targets.
 
 ## Stage 1 — Establish Validation And Captured-Rendering Benchmarks
 
+**Status: Complete (2026-10-09).** Maintained basic-validation, compiled
+rendering, and retained-output benchmarks are committed. The benchmark-only
+baseline is `0eb009ad5a3248e2a1e12cad9b3a05906d6b0850`; no production behavior
+changed.
+
 **Outcome:** Reproducible baselines for roadmap items 2 and 3; no production
 change in this stage.
 
@@ -509,10 +515,66 @@ rather than rerunning merely to create the final commit.
 
 ## Execution Evidence
 
-Implementation has not started. Record benchmark-only baseline revisions,
-comparisons, ownership analysis, conditional decisions, and final verification
-here as the stages are completed. Keep the feature roadmap focused on target
-state and progress rather than duplicating the staged procedure.
+### Validation And Compiled-Rendering Baseline
+
+The benchmark-only baseline is commit
+`0eb009ad5a3248e2a1e12cad9b3a05906d6b0850` (`Add validation and rendering
+benchmarks`), on top of planning baseline
+`3fde1f6cbbc2cc5b3dc17779ba44e0af6cd8a836`. The measured source is unchanged
+from that commit. No production files changed.
+
+Environment: Linux/amd64, Intel Core i5-7260U @ 2.20 GHz, benchmark parallelism
+4; `go1.26.8`, module directive `go 1.26.0`, ConfigKit `v0.5.0`, JSON Schema
+`v6.0.2`, and the backend modules `v3.20260930.0`.
+
+Command (five 500 ms samples per benchmark, without the race detector):
+
+```sh
+GOTOOLCHAIN=local GOWORK=off GOPROXY=off GONOPROXY=none GOSUMDB=off \
+  go test -mod=readonly -run '^$' \
+  -bench 'Benchmark(BasicValidation|CompiledRendering|RetainedRenderedOutput|GoRendererArtifactReferences)$' \
+  -benchmem -benchtime=500ms -count=5 \
+  ./internal/validate ./internal/prompt
+```
+
+Times below list all five `ns/op` samples in command order, followed by median
+and range. Allocation figures are `B/op; allocs/op` (ranges where they varied).
+
+| Benchmark case | `ns/op` samples (median; range) | Allocations |
+| --- | --- | --- |
+| Basic validation, short text | 46.59, 44.98, 43.31, 46.23, 43.19 (44.98; 43.19–46.59) | 0; 0 |
+| Basic validation, 1 MiB nonempty | 193859, 329884, 418896, 386126, 378173 (378173; 193859–418896) | 1048576–1048577; 1 |
+| Basic validation, ~1 MiB whitespace | 1112498, 1100439, 1175913, 1290678, 1108746 (1112498; 1100439–1290678) | 1048592–1048595; 2 |
+| Basic validation, Unicode whitespace | 170.8, 164.2, 158.6, 159.2, 165.2 (164.2; 158.6–170.8) | 16; 1 |
+| Compiled rendering, small message | 3931, 8488, 2041, 1902, 2181 (2181; 1902–8488) | 1632; 20 |
+| Compiled rendering, 256 KiB artifact message | 285812, 380128, 655925, 664387, 537684 (537684; 285812–664387) | 1050656–1050713; 25 |
+| Compiled rendering, repeated across session/messages | 1870972, 1362368, 1142268, 1073474, 1173588 (1173588; 1073474–1870972) | 3945983–3946034; 74 |
+| `NewGoRenderer` fallback, one artifact reference | 407143, 629149, 522549, 562200, 470393 (522549; 407143–629149) | 1056409–1056477; 69–70 |
+| `NewGoRenderer` fallback, repeated references | 1439883, 1535813, 1300176, 1541795, 1416267 (1439883; 1300176–1541795) | 2897171–2897255; 157 |
+| Retained output, four 256 KiB rendered results | 398753, 392206, 384503, 380386, 406691 (392206; 380386–406691) | 1050702–1050724; 25–26 |
+
+For the retained-output benchmark, post-GC live-heap deltas above the same
+setup-only fixture were 1048272, 1050176, 1046032, 1049856, and 1049016 bytes
+(median 1049016; range 1046032–1050176). The batch contains four separately
+rendered 256 KiB messages. This is retained-heap evidence, not an inference
+from `B/op`; it includes result structure and allocator/runtime noise. The
+initial exploratory run exposed cross-count sink retention in the measurement
+baseline; the benchmark now clears prior sinks before measuring setup, and the
+recorded values are from the corrected committed fixture.
+
+The short validator case allocates nothing, while the 1 MiB nonempty body has
+about one response-sized allocation; the whitespace-only case also retains a
+small failure-result allocation. Compiled rendering provides separate small,
+artifact-sized, and repeated-reference baselines, with the existing parsing
+fallback reported for context. Several render timings show wide ranges on this
+machine, so the median/range—not any single run—are the comparison baseline.
+The retained-output results consistently remain near 1 MiB for four outputs.
+
+Focused verification passed: `go test -mod=readonly ./internal/validate
+./internal/prompt`. Record later before/after comparisons, ownership analysis,
+conditional decisions, and final verification in this section as the remaining
+stages complete. Keep the feature roadmap focused on target state and progress
+rather than duplicating the staged procedure.
 
 ## Open Questions