Feat: refine create and list operations for MCP dashboard (#8823)

### What problem does this PR solve?

Refine MCP dashboard create and list operations.

### Type of change

- [x] Refactoring

api/utils/mcp_server.py

@@ -0,0 +1,34 @@
+from api.db.db_models import MCPServer
+from rag.utils.mcp_tool_call_conn import MCPToolCallSession, close_multiple_mcp_toolcall_sessions
+
+
+def get_mcp_tools(mcp_servers: list[MCPServer], timeout: float | int = 10) -> tuple[dict, str]:
+    results = {}
+    tool_call_sessions = []
+    try:
+        for mcp_server in mcp_servers:
+            server_key = mcp_server.id
+
+            cached_tools = mcp_server.variables.get("tools", {})
+
+            tool_call_session = MCPToolCallSession(mcp_server, mcp_server.variables)
+            tool_call_sessions.append(tool_call_session)
+
+            try:
+                tools = tool_call_session.get_tools(timeout)
+            except Exception:
+                tools = []
+
+            results[server_key] = []
+            for tool in tools:
+                tool_dict = tool.model_dump()
+                cached_tool = cached_tools.get(tool_dict["name"], {})
+
+                tool_dict["enabled"] = cached_tool.get("enabled", True)
+                results[server_key].append(tool_dict)
+
+        # PERF: blocking call to close sessions — consider moving to background thread or task queue
+        close_multiple_mcp_toolcall_sessions(tool_call_sessions)
+        return results, ""
+    except Exception as e:
+        return {}, str(e)