fix(m3): AI-assist scope + confidence gate + grouped wood categories

- inference: _taxonomy_lists hands the model the synced species leaves + wood
  leaves + case-insensitive attribute terms (was furniture roots / empty)
- inference: CALL1_SEED pins exact flat schema + *_confidence keys, drops grade
- inference: _gate maps field->confidence key correctly (was species_id_confidence),
  reads nested shape as safety net, omits grade (METADATA-40)
- review.svelte: figure gets AI assist, grade dropped from AI (owner judgment)
- MultiSelect: grouped mode (parents non-selectable headers, selectable leaves)
- METADATA-40 updated: grade not suggested by Call 1

frontend/src/create/review/Review.svelte

@@ -30,7 +30,7 @@
 
   // --- Derived taxonomy option lists (resolve by slug, never hardcoded ids) ---
   let speciesOpts: Opt[] = [];
-  let woodCatOpts: Opt[] = [];
+  let woodCatGroups: import('./MultiSelect.svelte').Group[] = [];
   let edgeOpts: Opt[] = [];
   let figureOpts: Opt[] = [];
   let gradeOpts: Opt[] = [];
@@ -57,7 +57,17 @@
       return (attr?.terms ?? []).map((t) => ({ id: t.id, name: t.name, ai: false }));
     };
     speciesOpts = childrenOf(speciesGrouper).map((c) => ({ id: c.id, name: c.name, ai: false }));
-    woodCatOpts = childrenOf(wcatGrouper).map((c) => ({ id: c.id, name: c.name, ai: false }));
+    // Wood categories: parent/child grouped (METADATA-10 — parents group only, never
+    // assigned). Each direct child of `wcat` that has its own children becomes a parent
+    // group with those children as leaves; a child with no children is a leaf under the
+    // (implicit) top group. This keeps the full tree visible with non-selectable parents.
+    woodCatGroups = (childrenOf(wcatGrouper)).map((parent) => {
+      const kids = cats.filter((c) => c.parent_id === parent.id);
+      const leaves: Opt[] = kids.length
+        ? kids.map((c) => ({ id: c.id, name: c.name, ai: false }))
+        : [{ id: parent.id, name: parent.name, ai: false }];
+      return { parent: { id: parent.id, name: parent.name }, leaves };
+    });
     edgeOpts = termsOf('edge type');
     figureOpts = termsOf('figure');
     gradeOpts = termsOf('grade');
@@ -216,7 +226,7 @@
       }
       if (s.edge_type_term_id) edgeTypeId = s.edge_type_term_id;
       if (s.figure_term_ids) { figureIds = [...s.figure_term_ids]; recs.push(...s.figure_term_ids); }
-      if (s.grade_term_id) gradeId = s.grade_term_id;
+      // Grade is not AI-suggested (METADATA-40) — owner judgment. Do not auto-fill.
       aiRecommendations = recs;
       aiNote = recs.length ? `AI suggested ${recs.length} field${recs.length === 1 ? '' : 's'} — review & edit below.` : 'No confident AI suggestions.';
       await commitReview();
@@ -330,7 +340,7 @@
     <!-- Wood categories (multi, searchable list, AI-assist) -->
     <MultiSelect
       label="Wood categories"
-      options={woodCatOpts}
+      groups={woodCatGroups}
       selected={woodCatIds}
       placeholder="Choose wood categories"
       testid="wood-cat"
@@ -349,18 +359,21 @@
     </div>
 
     <!-- Figure (multi, searchable list, AI-assist) -->
-    <MultiSelect
-      label="Figure"
-      options={figureOpts}
-      selected={figureIds}
-      placeholder="Choose figure"
-      testid="figure"
-      onToggle={(id) => (figureIds = toggleMulti(figureIds, id))}
-    />
-
-    <!-- Grade / Thickness / Moisture (single, AI-assist) -->
     <div class="field">
-      <label class="lbl" for="grade">Grade <span class="ai">AI assist</span></label>
+      <label class="lbl">Figure <span class="ai">AI assist</span></label>
+      <MultiSelect
+        label="Figure"
+        options={figureOpts}
+        selected={figureIds}
+        placeholder="Choose figure"
+        testid="figure"
+        onToggle={(id) => (figureIds = toggleMulti(figureIds, id))}
+      />
+    </div>
+
+    <!-- Grade (single, owner judgment — NOT AI-assisted per METADATA-40) -->
+    <div class="field">
+      <label class="lbl" for="grade">Grade</label>
       <select id="grade" class="sel" data-testid="grade" bind:value={gradeId} on:change={commitReview}>
         <option value="">— select —</option>
         {#each gradeOpts as o (o.id)}<option value={o.id}>{o.name}</option>{/each}