Delete the residual internal/alerts/alerts.go catch-all and move its remaining ownership groups into config_facade, model, constants, metric_hooks, manager, default_config, lifecycle, and escalation files.
Keep compatibility aliases in the alerts package, preserve the type-alias identity test, add a default-config pointer isolation regression test, and record the new ownership split in the alerts subsystem contract.
Proof: git diff --check -- docs/release-control/v6/internal/subsystems/alerts.md internal/alerts
Proof: go test ./internal/alerts/... -run 'TestDefaultAlertConfigUsesIndependentBackupAlertOrphanedPointer|TestTypeAliasIdentity|TestSetMetricHooks|TestSetLicenseCheckerStoresChecker|TestHistoryManager_Stop|TestEscalationDisabledWhenAlertsDisabled|TestEscalationDisabledWhenActivationPending|TestEscalationDisabledWhenActivationSnoozed|TestEscalationSkipsWhenScheduleDisabled|TestEscalationSkipsAcknowledgedAlerts|TestEscalationAdvancesLevels|TestEscalationDoesNotRepeatSameLevel|TestEscalationUsesCallback' -count=1
Proof: go test ./internal/alerts/... -count=1
Proof: go test ./internal/api -run Alert -count=1
rcourtman