Revert "Refa: Chats /chat API to RESTFul (#13871)" (#13877)

### What problem does this PR solve?

This reverts commit 1a608ac411.

### Type of change

- [x] Other (please describe):

sdk/python/ragflow_sdk/modules/base.py

@@ -54,9 +54,5 @@ class Base:
         res = self.rag.put(path, json)
         return res
 
-    def patch(self, path, json):
-        res = self.rag.patch(path, json)
-        return res
-
     def __str__(self):
         return str(self.to_json())

sdk/python/ragflow_sdk/modules/chat.py

@@ -23,22 +23,50 @@ class Chat(Base):
     def __init__(self, rag, res_dict):
         self.id = ""
         self.name = "assistant"
-        self.icon = ""
-        self.dataset_ids = []
-        self.llm_id = None
-        self.llm_setting = {}
-        self.prompt_config = {}
-        self.similarity_threshold = 0.2
-        self.vector_similarity_weight = 0.3
-        self.top_n = 6
-        self.top_k = 1024
-        self.rerank_id = ""
+        self.avatar = "path/to/avatar"
+        self.llm = Chat.LLM(rag, {})
+        self.prompt = Chat.Prompt(rag, {})
         super().__init__(rag, res_dict)
 
+    class LLM(Base):
+        def __init__(self, rag, res_dict):
+            self.model_name = None
+            self.temperature = 0.1
+            self.top_p = 0.3
+            self.presence_penalty = 0.4
+            self.frequency_penalty = 0.7
+            self.max_tokens = 512
+            super().__init__(rag, res_dict)
+
+    class Prompt(Base):
+        def __init__(self, rag, res_dict):
+            self.similarity_threshold = 0.2
+            self.keywords_similarity_weight = 0.7
+            self.top_n = 8
+            self.top_k = 1024
+            self.variables = [{"key": "knowledge", "optional": True}]
+            self.rerank_model = ""
+            self.empty_response = None
+            self.opener = "Hi! I'm your assistant. What can I do for you?"
+            self.show_quote = True
+            self.prompt = (
+                "You are an intelligent assistant. Your primary function is to answer questions based strictly on the provided knowledge base."
+                "**Essential Rules:**"
+                "- Your answer must be derived **solely** from this knowledge base: `{knowledge}`."
+                "- **When information is available**: Summarize the content to give a detailed answer."
+                "- **When information is unavailable**: Your response must contain this exact sentence: 'The answer you are looking for is not found in the knowledge base!' "
+                "- **Always consider** the entire conversation history."
+            )
+            super().__init__(rag, res_dict)
+
     def update(self, update_message: dict):
         if not isinstance(update_message, dict):
             raise Exception("ValueError('`update_message` must be a dict')")
-        res = self.patch(f"/chats/{self.id}", update_message)
+        if update_message.get("llm") == {}:
+            raise Exception("ValueError('`llm` cannot be empty')")
+        if update_message.get("prompt") == {}:
+            raise Exception("ValueError('`prompt` cannot be empty')")
+        res = self.put(f"/chats/{self.id}", update_message)
         res = res.json()
         if res.get("code") != 0:
             raise Exception(res["message"])