fix(momo): block EC404 auto-open with end-to-end URL guard

- normalize URLs at write time (scheduler crawlers, routes) to drop
  javascript:/EC404/placeholder i_code (momo_/manual_/pchome_)
- add global click+auxclick guard in base.html and ewoooc_base.html
  that intercepts blocked MOMO URLs and redirects to safe i_code URL
- per-page dashboards reuse the same isLikelyMomoIcode validation
- /api/track_momo_link records blocked events for diagnosis
- ship sanitize_momo_urls.py to clean existing polluted DB rows

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

services/price_comparison.py

@@ -14,6 +14,7 @@ from typing import List, Dict, Optional, Tuple
 from dataclasses import dataclass, asdict
 from difflib import SequenceMatcher
 from datetime import datetime
+from utils.momo_url_utils import build_momo_product_url, normalize_momo_product_url
 
 logger = logging.getLogger(__name__)
 
@@ -182,6 +183,13 @@ class ProductNameParser:
         # 提取產品線和關鍵字
         product_line, keywords = self._extract_keywords(cleaned_name, brand)
 
+        safe_product_url = (
+            normalize_momo_product_url(product_url, product_id)
+            if source == 'momo'
+            else product_url
+        )
+        safe_product_url = safe_product_url or build_momo_product_url(product_id)
+
         return ParsedProduct(
             original_name=name,
             brand=brand,
@@ -192,7 +200,7 @@ class ProductNameParser:
             source=source,
             price=price,
             product_id=product_id,
-            product_url=product_url
+            product_url=safe_product_url
         )
 
     def _clean_name(self, name: str) -> str: