feat(setup): add done button and integrate NFO scan into initialization

- Add /api/setup/unresolved/done endpoint to mark phase complete
- NFO scan now runs after series sync during initialization
- Middleware redirects to /login after setup complete (was /loading)
- Done button allows skipping folder resolution with redirect to NFO scan phase

src/server/api/setup_endpoints.py

@@ -321,4 +321,56 @@ async def delete_unresolved_folder(
             detail=f"Unresolved folder not found: {folder_name}"
         )
     
-    return {"status": "success", "message": f"Deleted unresolved folder: {folder_name}"}
+    return {"status": "success", "message": f"Deleted unresolved folder: {folder_name}"}
+
+
+class DoneResponse(BaseModel):
+    """Response model for completing unresolved folders."""
+    status: str = Field(..., description="Operation status")
+    message: str = Field(..., description="Human-readable message")
+    count: int = Field(..., description="Number of folders marked as done")
+
+
+@router.post("/unresolved/done", response_model=DoneResponse)
+async def complete_unresolved_folders(
+    db=Depends(get_database_session),
+) -> DoneResponse:
+    """Mark all unresolved folders as handled and complete the unresolved phase.
+    
+    This endpoint:
+    1. Marks the unresolved phase as completed in config
+    2. Returns the count of folders that were handled
+    
+    After this, /setup/unresolved will redirect to /loading.
+    
+    Returns:
+        DoneResponse with status and count of handled folders
+    """
+    from src.server.services.config_service import get_config_service
+
+    # Get all unresolved folders
+    folders = await UnresolvedFolderService.get_all_unresolved(db)
+    count = len(folders)
+    
+    # Mark unresolved as completed in config
+    config_service = get_config_service()
+    try:
+        config = config_service.load_config()
+        if config.other is None:
+            config.other = {}
+        config.other['unresolved_completed'] = True
+        config_service.save_config(config, create_backup=False)
+        logger.info("Marked unresolved phase as completed")
+    except Exception as e:
+        logger.warning("Failed to save unresolved_completed flag: %s", e)
+    
+    logger.info(
+        "Completed unresolved phase: %d folders handled",
+        count
+    )
+    
+    return DoneResponse(
+        status="success",
+        message=f"Marked {count} folders as handled. Unresolved phase completed.",
+        count=count,
+    )