Show total items to scan in progress overlay

- Add total_items parameter to broadcast_scan_started and broadcast_scan_progress
- Pass total from SeriesApp to WebSocket broadcasts in AnimeService
- Update JS overlay to show progress bar and current/total count
- Add CSS for progress bar styling
- Add unit tests for new total_items parameter
- All 1024 tests passing

src/server/services/websocket_service.py

@@ -498,27 +498,36 @@ class WebSocketService:
         }
         await self._manager.send_personal_message(message, connection_id)
 
-    async def broadcast_scan_started(self, directory: str) -> None:
+    async def broadcast_scan_started(
+        self, directory: str, total_items: int = 0
+    ) -> None:
         """Broadcast that a library scan has started.
         
         Args:
             directory: The root directory path being scanned
+            total_items: Total number of items to scan (for progress display)
         """
         message = {
             "type": "scan_started",
             "timestamp": datetime.now(timezone.utc).isoformat(),
             "data": {
                 "directory": directory,
+                "total_items": total_items,
             },
         }
         await self._manager.broadcast(message)
-        logger.info("Broadcast scan_started", directory=directory)
+        logger.info(
+            "Broadcast scan_started",
+            directory=directory,
+            total_items=total_items,
+        )
 
     async def broadcast_scan_progress(
         self,
         directories_scanned: int,
         files_found: int,
         current_directory: str,
+        total_items: int = 0,
     ) -> None:
         """Broadcast scan progress update to all clients.
         
@@ -526,6 +535,7 @@ class WebSocketService:
             directories_scanned: Number of directories scanned so far
             files_found: Number of MP4 files found so far
             current_directory: Current directory being scanned
+            total_items: Total number of items to scan (for progress display)
         """
         message = {
             "type": "scan_progress",
@@ -534,6 +544,7 @@ class WebSocketService:
                 "directories_scanned": directories_scanned,
                 "files_found": files_found,
                 "current_directory": current_directory,
+                "total_items": total_items,
             },
         }
         await self._manager.broadcast(message)