fix: return node evaluation errors to trigger reconcile retries

[Nesar976]

This change ensures that node evaluation failures are propagated back to the reconcile loop instead of being silently ignored.

Previously, transient failures during rule evaluation or taint patching were only logged internally, preventing controller-runtime from requeueing the reconcile request.

This PR:

• aggregates evaluation/status update errors
• returns reconcile errors properly for retry/backoff handling
• preserves existing behavior by continuing evaluation across rules
• adds test coverage for aggregated reconcile failures

Related Issue

Fixes #220

Type of Change

/kind bug

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The committers listed above are authorized under a signed CLA.

• ✅ login: Nesar976 / name: Nesar Kavri (26f190c, 55de513)
• ✅ login: Nesar976 / name: Nesar976 (32ff85d)
• ✅ login: sujalshah-bit / name: Sujal Shah (26f190c, 55de513)

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[sujalshah-bit]

Thanks for the PR @Nesar976 .

I think returning aggregated errors here improves convergence semantics because previously transient failures (patch conflicts, API timeouts, status update failures, etc.) could get logged and then effectively lost without another reconcile trigger.

One concern though is that we're currently aggregating all errors:

errs = append(errs, err)
...
return errors.Join(errs...)

Since Reconcile() returns that error directly, controller-runtime will requeue the node reconcile for any failure, including potentially non-retryable/business-logic errors.

For example:

• transient API/conflict errors → retry makes sense
• invalid rule configuration / unsupported evaluation state → retry likely won't help

With the current approach, a permanently failing rule could keep causing unnecessary reconcile retries for the node.

Would it make sense to distinguish retryable/system errors from expected rule evaluation failures and only return the retryable ones while still recording all failures in status/events/metrics?

Also, sign CLA :)

[ajaysundark]

/ok-to-test

[ajaysundark]

looks like this PR is duplicate to #222