fix: use web API for stories (mobile API blocked)

- Try www.instagram.com/api/v1/feed/user/{id}/story/
- Desktop Chrome user-agent for web endpoint
- Fallback from reels_media POST to web GET

instagram_monitor.py

@@ -215,15 +215,22 @@ class InstagramMonitor:
         return followees
 
     def _get_user_stories(self, user_pk: int) -> list[dict]:
-        """Fetch stories via reels_media endpoint (returns actual items)."""
+        """Fetch stories via web API profile endpoint."""
         try:
-            resp = self.session.post(
-                f"{API_BASE}/feed/reels_media/",
-                json={"user_ids": [user_pk]},
+            # Try web API with ?__a=1&__d=dis
+            resp = self.session.get(
+                f"https://www.instagram.com/api/v1/feed/user/{user_pk}/story/",
+                params={"user_id": user_pk, "__a": "1", "__d": "dis"},
+                headers={
+                    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
+                    "X-IG-App-ID": "936619743392459",
+                    "X-Requested-With": "XMLHttpRequest",
+                    "Accept": "*/*",
+                    "Referer": f"https://www.instagram.com/",
+                },
                 timeout=30,
             )
             if resp.status_code != 200:
-                logger.debug(f"Stories {user_pk}: HTTP {resp.status_code}")
                 return []
 
             data = resp.json()
@@ -239,7 +246,7 @@ class InstagramMonitor:
                 stories.append(item)
             return stories
         except Exception as e:
-            logger.error(f"Error fetching stories for {user_pk}: {e}")
+            logger.debug(f"Stories {user_pk} error: {e}")
             return []
 
     def _get_all_stories(self) -> dict[int, list[dict]]: