Expose Limitador reservation flags via CR (spec.reservations)

[eguzki]

Summary

Surface the new Limitador reservation server flags declaratively on the Limitador CR, so operators don't hand-manage container args.

Design: RFC 0021, reference-level section "Limitador-level opt-out".

Depends on: Kuadrant/limitador#506 (reservation flags --disable-reservations, --max-reservation-fraction, --max-reservation-ttl).

Acceptance Criteria

• Limitador CR field spec.reservations.enabled (bool, default true); when false, operator passes --disable-reservations to the generated container
• Limitador CR field spec.reservations.maxFraction (float, default 0.5); passed through as --max-reservation-fraction when non-default
• Limitador CR field spec.reservations.maxTtl (duration, default 60s); passed through as --max-reservation-ttl when non-default
• CRD schema/docs updated
• Unit tests for reconciliation of default vs. non-default values
• E2e test covering enabled: false disabling the flag end-to-end

Notes for reviewers

PR description should include: how to review, and manual verification (deploy a Limitador CR with spec.reservations set, confirm generated container args).