The flask spec generates local spec. While it will be very useful if we can update the local spec automatically when the spec changes.

We already have a LOCAL_SPEC_PATH config to get the path. Now we need to add a new config as the sync switch:

SYNC_LOCAL_SPEC: t.Optional[bool] = None

Problems:

• How to make sure the path is relative to the user's project root, and consistent with flask spec --output ....