Refine DocIndexRetriever READMEs (opea-project#2180)

Signed-off-by: Yi Yao <yi.a.yao@intel.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: alexsin368 <alex.sin@intel.com>

Author: 3 people

DocIndexRetriever/README.md

@@ -68,37 +68,14 @@ flowchart LR
 
 ```
 
-## We provided DocRetriever with different deployment infra
+## Deployment Options
 
-- [docker xeon version](docker_compose/intel/cpu/xeon/README.md) => minimum endpoints, easy to setup
-- [docker gaudi version](docker_compose/intel/hpu/gaudi/README.md) => with extra tei_gaudi endpoint, faster
+The table below lists currently available deployment options. They outline in detail the implementation of this example on selected hardware.
 
-## We allow users to set retriever/reranker hyperparams via requests
-
-Example usage:
-
-```python
-url = "http://{host_ip}:{port}/v1/retrievaltool".format(host_ip=host_ip, port=port)
-payload = {
-    "messages": query,  # must be a string, this is a required field
-    "k": 5,  # retriever top k
-    "top_n": 2,  # reranker top n
-}
-response = requests.post(url, json=payload)
-```
-
-**Note**: `messages` is the required field. You can also pass in parameters for the retriever and reranker in the request. The parameters that can changed are listed below.
-
-    1. retriever
-    * search_type: str = "similarity"
-    * k: int = 4
-    * distance_threshold: Optional[float] = None
-    * fetch_k: int = 20
-    * lambda_mult: float = 0.5
-    * score_threshold: float = 0.2
-
-    2. reranker
-    * top_n: int = 1
+| Category               | Deployment Option | Guide                                                                               |
+| ---------------------- | ----------------- | ----------------------------------------------------------------------------------- |
+| On-premise Deployments | Docker compose    | [DocIndexRetriever deployment on Xeon](./docker_compose/intel/cpu/xeon/README.md)   |
+|                        |                   | [DocIndexRetriever deployment on Gaudi](./docker_compose/intel/hpu/gaudi/README.md) |
 
 ## Validated Configurations