T1.6: Protocol version negotiation in handshake

docs/PRD/reports/T1.5.2-report.md

@@ -1,10 +1,10 @@
 # T1.5.2 — Workspace clippy hygiene + document pre-existing debt
 
-**Status:** Pending Review
+**Status:** Approved
 **Agent:** Kimi Code CLI
 **Started:** 2026-05-11T10:15Z
 **Completed:** 2026-05-11T10:20Z
-**Commit:** d8f8935
+**Commit:** 5cdb501
 **PRD:** ../PRD-wire-format-v2.md (process)
 
 ## What I changed
@@ -55,8 +55,14 @@ $ cargo clippy --workspace --all-targets -- -D warnings 2>&1 | grep -E "^error\b
 
 ## Reviewer checklist (filled in by reviewer)
 
-- [ ] Code matches PRD intent
-- [ ] Verification output is real (re-run if suspicious)
-- [ ] No backward-incompat surprises
-- [ ] Tests cover the new behavior
-- [ ] Approved
+- [x] Code matches PRD intent — PROTOCOL-AUDIT.md known-debt section present with accurate per-crate breakdown; report template updated; standard #3 amended
+- [x] Verification output is real — re-confirmed the section, template wording, and 12-error count
+- [x] No backward-incompat surprises — docs-only
+- [x] Tests cover the new behavior — n/a (docs)
+- [x] Approved
+
+### Reviewer notes (2026-05-11)
+
+Approved. Skipping the optional `tools/` script was the right call — a 12-error table is self-documenting; a script for it would be over-engineering. Standard #3 amendment ("Pre-existing debt in other crates [...] is not your problem") is a clean, narrow exception that protects agents without weakening the rule.
+
+One forward note: the eventual `wzp-codec` hygiene work should fix all 9 errors in one focused commit — they're mechanical (`saturating_sub`, `div_ceil`, `clamp`, etc.) and want a single coherent change. Implicit in the "Policy" line of the new section; consider promoting to an explicit Wave-6 or post-V1 task entry when planning the next backlog.