Add VRAM cleanup before loading image models

- Cleanup any existing models (text, audio, etc.) from VRAM before loading
  image models to prevent out of memory errors when switching between model types
- Applied to both diffusers and stable-diffusion-cpp loading paths

coderai

@@ -3629,6 +3629,25 @@ async def create_image_generation(request: ImageGenerationRequest, http_request:
     
     # Try diffusers first (torch-based, best quality for NVIDIA)
     # Skip if it's a GGUF model (those need stable-diffusion-cpp)
+    # First, cleanup any other models to free VRAM
+    for key in list(multi_model_manager.models.keys()):
+        # Skip image models
+        if key.startswith("image:"):
+            continue
+        # Unload any other model (text, audio, etc.) to free VRAM
+        model_to_cleanup = multi_model_manager.models.get(key)
+        if model_to_cleanup is not None:
+            print(f"Unloading '{key}' from VRAM to make room for diffusers image model")
+            try:
+                if hasattr(model_to_cleanup, 'cleanup') and callable(getattr(model_to_cleanup, 'cleanup')):
+                    model_to_cleanup.cleanup()
+                elif hasattr(model_to_cleanup, 'model') and model_to_cleanup.model is not None:
+                    if hasattr(model_to_cleanup.model, 'cleanup'):
+                        model_to_cleanup.model.cleanup()
+            except Exception as e:
+                print(f"Warning during cleanup of '{key}': {e}")
+            del multi_model_manager.models[key]
+    
     try:
         import torch
         from diffusers import StableDiffusionXLPipeline, DiffusionPipeline
@@ -3740,6 +3759,27 @@ async def create_image_generation(request: ImageGenerationRequest, http_request:
                 except ImportError:
                     pass
     
+    # If no cached image model found, need to load one - first cleanup any existing models
+    if sd_model is None:
+        # Check if there's a text model loaded and unload it to free VRAM
+        for key in list(multi_model_manager.models.keys()):
+            # Skip image models
+            if key.startswith("image:"):
+                continue
+            # Unload any other model (text, audio, etc.) to free VRAM
+            model_to_cleanup = multi_model_manager.models.get(key)
+            if model_to_cleanup is not None:
+                print(f"Unloading '{key}' from VRAM to make room for image model")
+                try:
+                    if hasattr(model_to_cleanup, 'cleanup') and callable(getattr(model_to_cleanup, 'cleanup')):
+                        model_to_cleanup.cleanup()
+                    elif hasattr(model_to_cleanup, 'model') and model_to_cleanup.model is not None:
+                        if hasattr(model_to_cleanup.model, 'cleanup'):
+                            model_to_cleanup.model.cleanup()
+                except Exception as e:
+                    print(f"Warning during cleanup of '{key}': {e}")
+                del multi_model_manager.models[key]
+    
     if sd_model is not None:
         # Check if it's a stable-diffusion-cpp model (has generate method from sd.cpp)
         try: