fix(user-lifecycle): track last-run state in core, not in audit log

The "Last run" KPI tile stayed empty after a manual policy run, even
though the run completed successfully. Two distinct bugs were
involved:

1. The dashboard read latestSystemRun() from the audit log filtered by
   trigger_type='system'. UserLifecycleService::run() never sets that
   value — it uses 'manual' for actor-triggered runs and 'cron' for
   scheduled ones. The query never matched anything.

2. Even with the right trigger_type, the audit log only writes per-user
   entries (logDeactivate / logDelete / logDeleteFailure). A run that
   processes zero users — including most cron ticks on a healthy
   tenant — leaves no trace, so the tile would still show "—" after a
   correct execution.

Both bugs share one root cause: run-trigger state was being inferred
from audit-log details, but those are two semantically different
things. Audit log answers "what did the run do?". A "last run" tile
answers "did the run happen?".

This commit moves run-trigger state to the core settings table and
keeps the audit log strictly for per-user events:

* Two new keys in core/Service/Settings/SettingKeys —
  USER_LIFECYCLE_LAST_RUN_AT_KEY and USER_LIFECYCLE_LAST_RUN_STATUS_KEY.
* SettingsUserLifecycleGateway gains recordLastRun() and getLastRun().
  UserSettingsGateway exposes them as recordLifecycleLastRun() /
  getLifecycleLastRun() so UserLifecycleService can call through its
  existing dependency without growing its constructor.
* UserLifecycleService::run() writes both keys in finally — every time
  the lock was acquired, regardless of whether any user was processed
  and regardless of whether the run finished cleanly. Status reflects
  $result['ok'] ('success' / 'failed').
* UserLifecyclePolicyDashboardService gains a lastRun() reader. Action
  page now sources the KPI tile from this core service instead of the
  audit interface — so the tile works even when the audit module is
  disabled.
* The audit-side lastRun() / latestSystemRun() / their tests are
  removed (YAGNI). Phase 4 (activity feed) can rebuild from the audit
  filter grid without a special method.

Behaviorally: a no-op run now records "Last run: just now · ✓ Success"
in the cockpit, exactly as expected.

All six quality gates green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

modules/audit/lib/Module/Audit/Repository/UserLifecycleAuditRepository.php

@@ -278,35 +278,6 @@ class UserLifecycleAuditRepository
         return (int) $updated > 0;
     }
 
-    /**
-     * Most recent system-triggered lifecycle run (any status), used by the policy dashboard tile.
-     *
-     * @return array{created_at:string,status:string,action:string}|null
-     */
-    public function latestSystemRun(): ?array
-    {
-        $row = DB::selectOne(
-            'select created_at, status, action
-             from user_lifecycle_audit_log
-             where trigger_type = ?
-             order by created_at desc
-             limit 1',
-            UserLifecycleTriggerType::System->value
-        );
-        if (!is_array($row)) {
-            return null;
-        }
-        $item = $row['user_lifecycle_audit_log'] ?? $row;
-        if (!is_array($item) || !isset($item['created_at'])) {
-            return null;
-        }
-        return [
-            'created_at' => (string) $item['created_at'],
-            'status' => (string) ($item['status'] ?? ''),
-            'action' => (string) ($item['action'] ?? ''),
-        ];
-    }
-
     /**
      * Count audit-log events for a single action+status within the last $days days (UTC).
      */