spec(0063): v0.2.0 — in-buffer pending review (D18, resolves Q2/Q7), evolve-in-place packaging (D17, resolves Q1), comments-first ask (D19), D11→shipped reality (D21), rung-2 spike findings recorded

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

specs/coauthoring-feasibility-spike.md

@@ -9,10 +9,27 @@ status: draft
 | **Type** | Throwaway discovery **prototype** (handbook §5.3) — code is disposable |
 | **Goal** | Prove the API-dependent design assumptions on the **real** VS Code surfaces, cheaply, **before** the full build — so post-ship iteration is polish, not design |
 | **Non-goal** | Production code, real Claude/SDK wiring (except E4), persistence durability, polish, breadth |
-| **Status** | `draft` |
+| **Status** | `draft` — **in progress: E1/E3/E5 done, E2/E4 remain** |
 
 ---
 
+## Status (2026-07-01, session 0063)
+
+Three of the five experiments are built and passed in `vscode-cowriting-prototype`:
+
+- **E1 — PASS with pivot.** VS Code does **not** render extension CodeLens inside
+  a diff editor; per-hunk CodeLens works in a normal editor, and tweak-then-Keep
+  attributes machine words vs. writer edits correctly. Folded back into the
+  Solution Design as **D18** (the review surface is the live buffer itself,
+  in-buffer pending changes — see `coauthoring-native-surfaces.md` v0.2.0).
+- **E3 — PASS.** The `markdown-it` contribution renders author-colored marks +
+  deletions in the built-in preview, theme-aware, with a working toggle.
+- **E5 — PASS.** Title-bar + status-bar entry points read as obvious without the
+  Source Control pane.
+- **E2 (baseline router: QuickDiff vs git `HEAD` + snapshot) and E4 (comment →
+  reply → offer → proposal) are not built yet** — now the riskiest unvalidated
+  assumptions and the spike's remaining work.
+
 ## Why this exists
 
 Static mockups validated the *look* and *state coverage*; they prove **nothing**