feat(cache,worker): overhaul cache layer and add generation task lease recovery

- shared/cache: add Options/L1/async/metrics/prefix decorators, multi-key ops, Redis pool tuning, and JSON readthrough metrics
- worker-generate: claim tasks via DB lease + heartbeat, requeue stale queued tasks, expire dead leases with refund/cache invalidation
- tenant: version article cache keys so worker recovery invalidations propagate cleanly
- shared/config: expand Redis (pool/timeouts/TLS) and Generation (lease/recovery) configs with defaults

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

server/internal/bootstrap/bootstrap.go

@@ -126,7 +126,18 @@ func New(configPath string) (*App, error) {
 		cfg.RabbitMQ.DesktopDispatchMonitorPrefix + ".*.*",
 	}
 	desktopDispatch := stream.NewDesktopDispatchHub(mqClient, logger, desktopDispatchBindings)
-	appCache := cache.New(cfg.Cache.Driver, rdb)
+	appCache := cache.NewWithOptions(cfg.Cache.Driver, rdb, cache.Options{
+		Namespace:        cfg.Cache.Namespace,
+		JitterRatio:      cfg.Cache.JitterRatio,
+		MetricsEnabled:   cfg.Cache.MetricsEnabled,
+		AsyncFillEnabled: cfg.Cache.AsyncFillEnabled,
+		AsyncFillWorkers: cfg.Cache.AsyncFillWorkers,
+		AsyncFillBuffer:  cfg.Cache.AsyncFillBuffer,
+		AsyncFillTimeout: cfg.Cache.AsyncFillTimeout,
+		L1Enabled:        cfg.Cache.L1Enabled,
+		L1TTL:            cfg.Cache.L1TTL,
+		DeleteScanCount:  cfg.Cache.DeleteScanCount,
+	})
 	brandService := tenantapp.NewBrandService(pool, monitoringPool, auditLogs, cfg.BrandLibrary).WithCache(appCache)
 	monitoringService := tenantapp.NewMonitoringService(pool, monitoringPool, mqClient, cfg.MonitoringDispatch, cfg.BrandLibrary, logger).WithRedis(rdb)
 	kolProfiles := repository.NewKolProfileRepository(pool)