Make LossLessDefaulter selective to only prevent dropping fields outside of schema

[mimowo]

What would you like to be added:

Investigate making the LossLessDefaulter in Kueue to only prevent dropping fields outside of schema.
This is a follow up from the discussion: #3132 (comment)

And follow up to the issue: #2878

Why is this needed:

• Long term we may want to remove some fields in Kueue webhooks, and it would be hard with the current LossLessDefaulter
• Making LossLessDefaulter selective could possibly let us promote it as an opt-in defaulter in controller-runtime, allowing for:
  • reduced maintenance cost by moving from Kueue to controller-runtime
  • allow sharing the solution with other projects so that they don't need to reinvent the wheel

Completion requirements:

Investigate if this is feasible. and what is the implementation complexity, prototype.

[mimowo]

/assign @tenzen-y
per comment #3132 (comment)
/cc @alculquicondor

[tenzen-y]

Sorry. I did not want to indicate taking this issue.
/unassign

[mimowo]

Sorry, I misread your message which was clear. Thanks for clarifying!
Anyway, the issue is open for contributions.

[mbobrovskyi]

/assign

[mimowo]

/close
we don't need this in Kueue as there is fix in controller-runtime to be released, issue to track using the fix: #3469