feat(controller): add read-only mode to LifecycleManager

[aaronschweig]

This PR adds a readonly mode to the lifecycle controller that skips all eventual status update to work with initializing workspaces in kcp.

[nexus49]

It would be great to add a check so that WithReadOnly and WithConditionManagement/WithSpreadReconcile cannot be used together.

[aaronschweig]

It would be great to add a check so that WithReadOnly and WithConditionManagement/WithSpreadReconcile cannot be used together.

Done I implemented it in here:

golang-commons/controller/lifecycle/lifecycle.go

Lines 426 to 428 in 79a1a88

	if (l.manageConditions || l.spreadReconciles) && l.readOnly {
	return nil, fmt.Errorf("cannot use conditions or spread reconciles in read-only mode")
	}