feat(clickhouse): wire batchwriter into business ingestion paths

Migrate risk_control audit logs to internal/db/batchwriter and add
openflare/chwriter with per-table async flush for observability
timeseries and node access logs.

Replace single-row ClickHouse inserts and pre-insert SELECT count()
dedup with repository BatchInsert* APIs, in-process TTL dedup for
metric/report snapshots, and bootstrap initialization on API startup.

internal/bootstrap/bootstrap.go

@@ -11,6 +11,7 @@ import (
 
 	admin_push "github.com/Rain-kl/Wavelet/internal/apps/admin/push"
 	"github.com/Rain-kl/Wavelet/internal/apps/admin/push/custom_events"
+	"github.com/Rain-kl/Wavelet/internal/apps/openflare/chwriter"
 	"github.com/Rain-kl/Wavelet/internal/apps/risk_control"
 	taskhandlers "github.com/Rain-kl/Wavelet/internal/task/handlers"
 	"github.com/Rain-kl/Wavelet/pkg/logger"
@@ -83,6 +84,7 @@ func Init(ctx context.Context, opts Options) {
 		}
 		if opts.API {
 			risk_control.InitLogWriter(ctx)
+			chwriter.Init(ctx)
 		}
 	})
 }