phase: 124_image_chips_and_answers

All green. Final report:

**Phase 124 final verification pass — all criteria verified, no defects found (nothing to fix)**
- Verified the implemented phase (all 7 tasks done, changes in working tree): `BOR_ANSWER_IMAGES` toggle, `show_image` tool + refusals + `holder.shown_images`, toggle-gated prompt clause, `answer_image` frame field (None-omitting serializer) + `ChatMessage` persistence, `merge_cited_docs` auto-cite bug fix, answer-figure UI (live/restore/shared/CSS), mock triggers + E2E suite. Also confirmed the bytes route → public change matches the phase-123 shared-chat precedent (task 06 design).
- `uv run pytest --cov=app --cov-report=term-missing` → **2848 passed**, TOTAL **99%** (>90% gate)
- `bash .agents/validate.sh` → **validation OK** (tests + coverage + ruff + pyright)
- `uv run ruff check . && uv run pyright` → clean, 0 errors
- `uv run pytest tests/e2e/test_answer_images.py -v --no-cov` (isolated) → **5/5 passed**
- Mock-inert spot checks: `tests/e2e/test_image_documents.py` 4/4, `tests/e2e/test_agent_document_tools.py` 4/4

**Completion criteria:** ① zero-read suggested-tier image doc chips with figure — verified (unit matrix, integration `test_zero_read_grounded_turn_auto_cites_suggested_image_doc`, E2E bug-fix flows); ② show_image → answer figure below text/above chips, second call refused, persists + restore + shared — verified (unit handler matrix, integration round-trip, E2E feature flow); ③ default-off byte-identical (3 tools, no clause, no key) — verified (unit + integration + E2E toggle-off); ④ full suite green / >90% / lint clean — verified above; ⑤ commit + phase move — harness responsibility (changes left uncommitted in working tree, no live-infrastructure changes made).

**Next pending phase:** none — `todo/` holds only this phase; the pipeline is clear once the harness moves it.

frontend/assets/shared.js

@@ -349,6 +349,50 @@ function addBubbleImage(wrap, src, alt) {
   bubble.prepend(img);
 }
 
+/* The brain answer's image (phase 124, task 06, TODO L3) — the local
+ * copy of the chat page's appendAnswerImage (the per-page duplication
+ * house style: this file keeps its own small copies of the chat
+ * page's message-fragment builders). NON-INTERACTIVE like every other
+ * shared-page fragment (owner-locked zero controls: no link, no
+ * modal, no click handler — a plain <figure>, unlike the chat page's
+ * anchor). The bytes route is PUBLIC (the token is the shared chat's
+ * credential, like the phase-123 user-image contract), so the img
+ * loads for guests exactly as it does for the owner. The visible
+ * caption keeps the document's TITLE: the content endpoint the chat
+ * page fetches for the summary is user-gated (a guest fetch would
+ * just 401), and a caption is ALWAYS visible either way (the WCAG
+ * alt contract holds with the title standing in). A failed load
+ * REMOVES the figure (the collapse rule — never a broken-image
+ * icon). */
+function addAnswerImage(wrap, ref) {
+  if (
+    !ref ||
+    typeof ref.source !== "string" ||
+    typeof ref.path !== "string" ||
+    typeof ref.image_url !== "string" ||
+    !ref.image_url
+  ) {
+    return; // no ref (or a malformed one) → no figure DOM at all
+  }
+  const body = wrap?.querySelector?.(".msg-body");
+  if (!body) return;
+  const title =
+    typeof ref.title === "string" && ref.title ? ref.title : "image";
+  const fig = document.createElement("figure");
+  fig.className = "answer-image";
+  const img = document.createElement("img");
+  img.className = "answer-image-img";
+  img.src = ref.image_url; // the public bytes route
+  img.loading = "lazy";
+  img.alt = title;
+  img.addEventListener("error", () => fig.remove()); // collapse: never a broken icon
+  const caption = document.createElement("span");
+  caption.className = "answer-image-caption";
+  caption.textContent = title; // the visible caption (always)
+  fig.append(img, caption);
+  body.appendChild(fig);
+}
+
 /* One stored record through the SAME .msg structure the chat page
  * uses (pixel-parity with the chat page's restore path): user → the
  * .msg.user bubble (with the question's attached image when the
@@ -356,9 +400,11 @@ function addBubbleImage(wrap, src, alt) {
  * .msg.brain bubble with the optional
  * thinking block (restored COLLAPSED — phase 17), the tool lines,
  * the deflection treatment + the plain-text "Maybe try" chips, the
- * plain-text source chips, and the stopped note. NO interactive
- * markup is ever created here — no buttons, no forms, no links, no
- * click handlers (owner-locked: zero controls). Markdown goes
+ * brain answer's image figure (phase 124, task 06 — a plain
+ * non-interactive <figure>), the plain-text source chips, and the
+ * stopped note. NO interactive markup is ever created here — no
+ * buttons, no forms, no links, no click handlers (owner-locked:
+ * zero controls). Markdown goes
  * through the global escape-first renderMarkdown (markdown.js): the
  * stored payloads are raw text, so the renderer's XSS safety applies
  * unchanged. */
@@ -385,6 +431,11 @@ function renderSharedMessage(m) {
     wrap.classList.add("is-deflected");
     addMaybeTry(wrap, m.suggestions);
   }
+  // Phase 124 (task 06, TODO L3): the answer image renders with the
+  // brain bubble — the SAME A4 position as the chat page's render
+  // (below the text, above the chip row). A record without the key
+  // renders byte-identically (no figure DOM).
+  addAnswerImage(wrap, m.answer_image);
   addSources(wrap, m.sources);
   if (m.stopped) addStoppedNote(wrap);
 }