Add per-product AI verification disable option

Users can now disable AI verification for individual products that
AI is having trouble with (e.g., Amazon products where AI keeps
picking the main buy box price instead of "other sellers").

Changes:
- Add ai_verification_disabled column to products table
- Add toggle in product detail page under "Advanced Settings"
- Pass skip flag to scrapeProductWithVoting
- Skip AI verification when flag is set

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/api/client.ts

@@ -65,6 +65,7 @@ export interface Product {
   price_drop_threshold: number | null;
   target_price: number | null;
   notify_back_in_stock: boolean;
+  ai_verification_disabled: boolean;
   created_at: string;
   current_price: number | null;
   currency: string | null;
@@ -131,6 +132,7 @@ export const productsApi = {
     price_drop_threshold?: number | null;
     target_price?: number | null;
     notify_back_in_stock?: boolean;
+    ai_verification_disabled?: boolean;
   }) => api.put<Product>(`/products/${id}`, data),
 
   delete: (id: number) => api.delete(`/products/${id}`),

frontend/src/pages/ProductDetail.tsx

@@ -30,6 +30,7 @@ export default function ProductDetail() {
   const [priceDropThreshold, setPriceDropThreshold] = useState<string>('');
   const [targetPrice, setTargetPrice] = useState<string>('');
   const [notifyBackInStock, setNotifyBackInStock] = useState(false);
+  const [aiVerificationDisabled, setAiVerificationDisabled] = useState(false);
 
   const REFRESH_INTERVALS = [
     { value: 300, label: '5 minutes' },
@@ -62,6 +63,7 @@ export default function ProductDetail() {
         setTargetPrice(productRes.data.target_price.toString());
       }
       setNotifyBackInStock(productRes.data.notify_back_in_stock || false);
+      setAiVerificationDisabled(productRes.data.ai_verification_disabled || false);
     } catch {
       setError('Failed to load product details');
     } finally {
@@ -139,12 +141,14 @@ export default function ProductDetail() {
         price_drop_threshold: threshold,
         target_price: target,
         notify_back_in_stock: notifyBackInStock,
+        ai_verification_disabled: aiVerificationDisabled,
       });
       setProduct({
         ...product,
         price_drop_threshold: threshold,
         target_price: target,
         notify_back_in_stock: notifyBackInStock,
+        ai_verification_disabled: aiVerificationDisabled,
       });
       showToast('Notification settings saved');
     } catch {
@@ -763,6 +767,114 @@ export default function ProductDetail() {
           </div>
         </>
       )}
+
+      <style>{`
+        .advanced-settings-card {
+          background: var(--surface);
+          border-radius: 0.75rem;
+          box-shadow: var(--shadow);
+          padding: 1.5rem;
+          margin-top: 2rem;
+        }
+
+        .advanced-settings-header {
+          display: flex;
+          align-items: center;
+          gap: 0.75rem;
+          margin-bottom: 1rem;
+        }
+
+        .advanced-settings-icon {
+          font-size: 1.5rem;
+        }
+
+        .advanced-settings-title {
+          font-size: 1.125rem;
+          font-weight: 600;
+          color: var(--text);
+        }
+
+        .advanced-settings-description {
+          color: var(--text-muted);
+          font-size: 0.875rem;
+          margin-bottom: 1.5rem;
+          line-height: 1.5;
+        }
+
+        .advanced-checkbox-group {
+          display: flex;
+          align-items: center;
+          gap: 0.75rem;
+          padding: 0.75rem;
+          background: var(--background);
+          border-radius: 0.375rem;
+          cursor: pointer;
+        }
+
+        .advanced-checkbox-group:hover {
+          background: var(--border);
+        }
+
+        .advanced-checkbox-group input[type="checkbox"] {
+          width: 1.125rem;
+          height: 1.125rem;
+          accent-color: var(--primary);
+          cursor: pointer;
+        }
+
+        .advanced-checkbox-label {
+          display: flex;
+          flex-direction: column;
+          gap: 0.125rem;
+        }
+
+        .advanced-checkbox-label span:first-child {
+          font-size: 0.875rem;
+          font-weight: 500;
+          color: var(--text);
+        }
+
+        .advanced-checkbox-label span:last-child {
+          font-size: 0.75rem;
+          color: var(--text-muted);
+        }
+
+        .advanced-settings-actions {
+          margin-top: 1rem;
+        }
+      `}</style>
+
+      <div className="advanced-settings-card">
+        <div className="advanced-settings-header">
+          <span className="advanced-settings-icon">⚙️</span>
+          <h2 className="advanced-settings-title">Advanced Settings</h2>
+        </div>
+        <p className="advanced-settings-description">
+          Fine-tune how price extraction works for this product.
+        </p>
+
+        <label className="advanced-checkbox-group">
+          <input
+            type="checkbox"
+            checked={aiVerificationDisabled}
+            onChange={(e) => setAiVerificationDisabled(e.target.checked)}
+          />
+          <div className="advanced-checkbox-label">
+            <span>Disable AI Verification</span>
+            <span>Prevent AI from "correcting" the scraped price. Useful when AI keeps picking the wrong price (e.g., main price instead of other sellers on Amazon).</span>
+          </div>
+        </label>
+
+        <div className="advanced-settings-actions">
+          <button
+            className="btn btn-primary"
+            onClick={handleSaveNotifications}
+            disabled={isSavingNotifications}
+          >
+            {isSavingNotifications ? 'Saving...' : 'Save Settings'}
+          </button>
+        </div>
+      </div>
     </Layout>
   );
 }