Migrate the MVP into kotaemon (#108)

- Migrate the MVP into kotaemon.
- Preliminary include the pipeline within chatbot interface.
- Organize MVP as an application.

Todo:

- Add an info panel to view the planning of agents -> Fix streaming agents' output.

Resolve: #60
Resolve: #61 
Resolve: #62

knowledgehub/indices/splitters/__init__.py

@@ -29,8 +29,19 @@ class TokenSplitter(LlamaIndexDocTransformerMixin, BaseSplitter):
 
 
 class SentenceWindowSplitter(LlamaIndexDocTransformerMixin, BaseSplitter):
-    def __init__(self, window_size: int = 3, **params):
-        super().__init__(window_size=window_size, **params)
+    def __init__(
+        self,
+        window_size: int = 3,
+        window_metadata_key: str = "window",
+        original_text_metadata_key: str = "original_text",
+        **params,
+    ):
+        super().__init__(
+            window_size=window_size,
+            window_metadata_key=window_metadata_key,
+            original_text_metadata_key=original_text_metadata_key,
+            **params,
+        )
 
     def _get_li_class(self):
         from llama_index.node_parser import SentenceWindowNodeParser