feat: Add new Microsoft based MCP server for OpenAPI using official packages (github#117)

Author: pomianowski

servers/openapi/server.yaml

@@ -0,0 +1,25 @@
+name: openapi
+image: mcp/openapi
+type: server
+meta:
+    category: productivity
+    tags:
+        - productivity
+about:
+    title: OpenAPI Toolkit for MCP
+    description: Fetch, validate, and generate code or curl from any OpenAPI or Swagger spec - all from a single URL.
+    icon: https://raw.githubusercontent.com/lepoco/openapi.client/refs/heads/main/build/nuget.png
+source:
+    project: https://github.com/lepoco/openapi.client
+    branch: main
+config:
+    description: Configure the connection to OpenAPI Toolkit for MCP
+    env:
+        - name: MODE
+          example: Stdio
+          value: '{{openapi.mode}}'
+    parameters:
+        type: object
+        properties:
+            mode:
+                type: string