feat(bte panel): real SKU dropdown + contextual CMO chat handoff

Tranche C — BTE basics.

1. SKU dropdown now sources from Adwright's TopRecipes (top-selling
   offerings) via /api/adwright/last-panel-update?tool=adwright_list_recipes
   instead of bundled PLACEHOLDER_SKUS. Falls back to placeholders on
   any failure. state.skus drives both the toolbar select build and the
   name lookups in _openCmoChat / requestPhotoshoot. _refreshSkuOptions
   rewrites the <option> set in place so the dropdown updates without
   rebuilding the toolbar.

2. _openCmoChat now pre-fills the chat textarea with the operator's
   current BTE setup (brand, mode, media, recipe family, SKU, variants,
   selected asset) so they don't retype context every iteration.
   Switch + setTimeout(200) lets the chat panel mount before set value
   + dispatch input event. Doesn't auto-send — operator reviews then
   hits send themselves.

C3 (seed assets) closed without code: BTE backend at localhost:6001
already serves 10 real assets (1 evaluated with brandFit 4.2 ★3.8,
2 approved with hasImageData=true, 5 requested). Original "placeholder"
complaint was about the SKU dropdown, not the asset grid.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

static/bte.js

@@ -48,6 +48,10 @@
     selected: null,      // asset id
     pollTimer: null,
     log: [],
+    // SKU options surfaced in the toolbar dropdown. Defaults to the bundled
+    // placeholders until _fetchSkuOptions replaces them with real top-selling
+    // offerings from Adwright's TopRecipes RPC.
+    skus: PLACEHOLDER_SKUS.slice(),
   };
 
   // ── Public namespace ─────────────────────────────────────────────────────
@@ -91,6 +95,37 @@
     }
     overlay.hidden = false;
     _refreshGrid();
+    _fetchSkuOptions();
+  }
+
+  // Pull top-selling offerings from Adwright (TopRecipes) so the SKU
+  // dropdown reflects what's actually shipping, not the bundled PLACEHOLDER
+  // list. Best-effort — falls through to placeholders on any failure.
+  function _fetchSkuOptions() {
+    fetch("/api/adwright/last-panel-update?session_id=&since=0&tool=adwright_list_recipes")
+      .then((r) => r.json())
+      .then((r) => {
+        const recipes = r && r.update && r.update.payload && r.update.payload.recipes;
+        if (!Array.isArray(recipes) || !recipes.length) return;
+        state.skus = recipes.map((rec) => ({
+          id: String(rec.product_id || rec.id || ""),
+          name: rec.name || "",
+        })).filter((s) => s.id && s.name);
+        _refreshSkuOptions();
+      })
+      .catch(() => { /* fallback: keep placeholders */ });
+  }
+
+  function _refreshSkuOptions() {
+    const sel = document.getElementById("svrntyBteSku");
+    if (!sel) return;
+    const current = sel.value;
+    let html = '<option value="">— pick SKU —</option>';
+    state.skus.forEach((s) => {
+      html += '<option value="' + _esc(s.id) + '">' + _esc(s.name) + "</option>";
+    });
+    sel.innerHTML = html;
+    if (current) sel.value = current;
   }
 
   function _closeOverlay() {
@@ -148,9 +183,10 @@
       state.family = v; _updateToolbarPressed(); _updateGenerateEnabled(); _refreshGrid();
     }));
 
-    // SKU dropdown
+    // SKU dropdown — populated from state.skus (placeholder at boot,
+    // replaced by real top-selling offerings via _fetchSkuOptions).
     const skuOpts = [{ value: "", label: "— pick SKU —" }].concat(
-      PLACEHOLDER_SKUS.map((s) => ({ value: s.id, label: s.name })));
+      state.skus.map((s) => ({ value: s.id, label: s.name })));
     bar.appendChild(_labeled("SKU", _select("svrntyBteSku", skuOpts, state.skuId || "", (v) => {
       state.skuId = v || null; _updateGenerateEnabled();
     })));
@@ -315,7 +351,7 @@
   // ── Generate flow ────────────────────────────────────────────────────────
   function _onGenerate() {
     if (!state.family || !state.skuId) return;
-    const sku = PLACEHOLDER_SKUS.find((s) => s.id === state.skuId);
+    const sku = state.skus.find((s) => s.id === state.skuId);
     const recipeLabel = `${state.family}__${state.mode}__${state.media}`;
     const body = {
       brandId: state.brand,
@@ -496,13 +532,35 @@
 
   // ── CMO chat handoff ─────────────────────────────────────────────────────
   function _openCmoChat() {
-    // Honest minimum: surface the WebUI chat panel (whichever profile is
+    // Pre-fill the chat textarea with BTE state context so the operator
-    // active). Full CMO-scoped iframe / component reuse is COMMAND-CENTER-PRD
+    // doesn't have to retype "I'm in BTE, brand Plan B, mode Polished, …".
-    // §6.5 Phase E — not v1 of this panel.
+    // Don't auto-send — user reviews + edits + hits send. Full CMO-scoped
+    // iframe is COMMAND-CENTER-PRD §6.5 Phase E (not v1).
+    const modeL = MODES.find((m) => m.slug === state.mode);
+    const familyL = FAMILIES.find((f) => f.slug === state.family);
+    const sku = state.skus.find((s) => s.id === state.skuId);
+    const lines = ["I'm working in BTE Command Center. Help me iterate."];
+    lines.push("- Brand: " + state.brand);
+    if (modeL) lines.push("- Mode: " + modeL.label);
+    lines.push("- Media: " + state.media);
+    if (familyL) lines.push("- Recipe family: " + familyL.label);
+    if (sku) lines.push("- SKU: " + sku.name);
+    lines.push("- Variants: " + state.variants);
+    if (state.selected) lines.push("- Selected asset: " + state.selected);
+    const prompt = lines.join("\n") + "\n\nWhat should I change next?";
+
     _closeOverlay();
     if (typeof window.switchPanel === "function") {
       try { window.switchPanel("chat", { fromRailClick: true }); } catch (_) { /* ignore */ }
     }
+    // Defer pre-fill so the chat panel + #msg textarea mount first.
+    setTimeout(() => {
+      const msg = document.getElementById("msg");
+      if (!msg) return;
+      msg.value = prompt;
+      try { msg.dispatchEvent(new Event("input", { bubbles: true })); } catch (_) {}
+      try { msg.focus(); } catch (_) {}
+    }, 200);
   }
 
   // ── Proxy helpers ────────────────────────────────────────────────────────