H4: NamespaceReconciler.reconcileMirror builds an ad-hoc SourceReconciler
to delegate mirror creation. The previous version left APIReader and
CircuitBreaker as nil, which silently disabled freshness verification
on the namespace-driven path (a label change to a target namespace
would mirror cached, possibly stale source data) and bypassed circuit
breaker accounting for those reconciles.
Construction extracted into newSourceReconciler so the forwarding is
covered by a unit test that pins both fields by identity.
C2: updateLastSyncStatus wrote the sync-status annotation on every
successful reconcile. Because the source's watch predicate is the
'enabled' label (server-side filter), that Update fires a watch event
that re-enters Reconcile. With reconciled/error counts varying across
cycles, the value differs each time, so the API server bumps RV and
the loop never quiesces. Now skips the Update when the value matches
the existing annotation.
C3: NamespaceReconciler's happy-path returned RequeueAfter=3s
unconditionally. Every namespace in the cluster re-reconciled every
3 seconds forever, generating constant List calls per source kind.
Now returns ctrl.Result{}; cache-staleness windows are handled by
the manager's resync period and source freshness verification.
lukaszraczylo