Add support for VolcEngine - the current version supports SDK2 (#885)

- The main idea is to assemble **ak**, **sk**, and **ep_id** into a
dictionary and store it in the database **api_key** field
- I don’t know much about the front-end, so I learned from Ollama, which
may be redundant.

### Configuration method

- model name

- Format requirements: {"VolcEngine model name":"endpoint_id"}
    - For example: {"Skylark-pro-32K":"ep-xxxxxxxxx"}
    
- Volcano ACCESS_KEY
- Format requirements: VOLC_ACCESSKEY of the volcano engine
corresponding to the model

- Volcano SECRET_KEY
- Format requirements: VOLC_SECRETKEY of the volcano engine
corresponding to the model
    
### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

api/db/init_data.py

@@ -132,7 +132,12 @@ factory_infos = [{
     "logo": "",
     "tags": "LLM",
     "status": "1",
-},
+},{
+    "name": "VolcEngine",
+    "logo": "",
+    "tags": "LLM, TEXT EMBEDDING",
+    "status": "1",
+}
     # {
     #     "name": "文心一言",
     #     "logo": "",
@@ -372,6 +377,21 @@ def init_llm_factory():
             "max_tokens": 16385,
             "model_type": LLMType.CHAT.value
         },
+        # ------------------------ VolcEngine -----------------------
+        {
+            "fid": factory_infos[9]["name"],
+            "llm_name": "Skylark2-pro-32k",
+            "tags": "LLM,CHAT,32k",
+            "max_tokens": 32768,
+            "model_type": LLMType.CHAT.value
+        },
+        {
+            "fid": factory_infos[9]["name"],
+            "llm_name": "Skylark2-pro-4k",
+            "tags": "LLM,CHAT,4k",
+            "max_tokens": 4096,
+            "model_type": LLMType.CHAT.value
+        },
     ]
     for info in factory_infos:
         try: