Create set_description endpoint (#693)

Create set_description endpoint


TSIA

## Test Plan
Follow dev README to setup the local editor:
https://github.com/lastmile-ai/aiconfig/tree/main/python/src/aiconfig/editor#dev,
then run this command
```
curl http://localhost:8080/api/set_description -d '{"description":"yo this is a cool new description get rekt dont @ me bro"}' -X POST -H 'Content-Type: application/json'
```


https://github.com/lastmile-ai/aiconfig/assets/151060367/0db278b3-8273-4178-8010-380538dcd0ca

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* __->__ #693
* #692
* #691
* #690
* #688
* #670
* #668

python/src/aiconfig/editor/server/server.py

@@ -285,3 +285,16 @@ def set_name() -> FlaskResponse:
     operation = make_op_run_method(MethodName("set_name"))
     operation_args: Result[OpArgs, str] = result.Ok(OpArgs({"name": name}))
     return run_aiconfig_operation_with_op_args(aiconfig, "set_name", operation, operation_args)
+
+
+@app.route("/api/set_description", methods=["POST"])
+def set_description() -> FlaskResponse:
+    state = get_server_state(app)
+    aiconfig = state.aiconfig
+    request_json = request.get_json()
+
+    description: str | None = request_json.get("description")
+
+    operation = make_op_run_method(MethodName("set_description"))
+    operation_args: Result[OpArgs, str] = result.Ok(OpArgs({"description": description}))
+    return run_aiconfig_operation_with_op_args(aiconfig, "set_description", operation, operation_args)