refactor: rename interrogate module to caption

Move all caption-related modules from modules/interrogate/ to modules/caption/
for better naming consistency:
- Rename deepbooru, deepseek, joycaption, joytag, moondream3, openclip, tagger,
  vqa, vqa_detection, waifudiffusion modules
- Add new caption.py dispatcher module
- Remove old interrogate.py (functionality moved to caption.py)

modules/caption/tagger.py

@@ -0,0 +1,79 @@
+# Unified Tagger Interface - Dispatches to WaifuDiffusion or DeepBooru based on model selection
+# Provides a common interface for the Booru Tags tab
+
+from modules import shared
+
+DEEPBOORU_MODEL = "DeepBooru"
+
+
+def get_models() -> list:
+    """Return combined list: DeepBooru + WaifuDiffusion models."""
+    from modules.caption import waifudiffusion
+    return [DEEPBOORU_MODEL] + waifudiffusion.get_models()
+
+
+def refresh_models() -> list:
+    """Refresh and return all models."""
+    return get_models()
+
+
+def is_deepbooru(model_name: str) -> bool:
+    """Check if selected model is DeepBooru."""
+    return model_name == DEEPBOORU_MODEL
+
+
+def load_model(model_name: str) -> bool:
+    """Load appropriate backend."""
+    if is_deepbooru(model_name):
+        from modules.caption import deepbooru
+        return deepbooru.load_model()
+    else:
+        from modules.caption import waifudiffusion
+        return waifudiffusion.load_model(model_name)
+
+
+def unload_model():
+    """Unload both backends to ensure memory is freed."""
+    from modules.caption import deepbooru, waifudiffusion
+    deepbooru.unload_model()
+    waifudiffusion.unload_model()
+
+
+def tag(image, model_name: str = None, **kwargs) -> str:
+    """Unified tagging - dispatch to correct backend.
+
+    Args:
+        image: PIL Image to tag
+        model_name: Model to use (DeepBooru or WaifuDiffusion model name)
+        **kwargs: Additional arguments passed to the backend
+
+    Returns:
+        Formatted tag string
+    """
+    if model_name is None:
+        model_name = shared.opts.waifudiffusion_model
+
+    if is_deepbooru(model_name):
+        from modules.caption import deepbooru
+        return deepbooru.tag(image, **kwargs)
+    else:
+        from modules.caption import waifudiffusion
+        return waifudiffusion.tag(image, model_name=model_name, **kwargs)
+
+
+def batch(model_name: str, **kwargs) -> str:
+    """Unified batch processing.
+
+    Args:
+        model_name: Model to use (DeepBooru or WaifuDiffusion model name)
+        **kwargs: Additional arguments passed to the backend
+
+    Returns:
+        Combined tag results
+    """
+    if is_deepbooru(model_name):
+        from modules.caption import deepbooru
+        return deepbooru.batch(model_name=model_name, **kwargs)
+    else:
+        from modules.caption import waifudiffusion
+        return waifudiffusion.batch(model_name=model_name, **kwargs)