[Feature Request] LWS needs status.observedGeneration field.

[veophi]

What would you like to be added:
lws.status.observedGeneration field.

Why is this needed:
See https://alenkacz.medium.com/kubernetes-operator-best-practices-implementing-observedgeneration-250728868792

Completion requirements:

1. add status.observedGeneration field for lws.
2. update this field if lws.metadata.generation was changed.

This enhancement requires the following artifacts:

• Design doc
• API change
• Docs update

The artifacts should be linked in subsequent comments.