Make snapshot projections self-diagnosing

cmd/agent/main.go

@@ -296,6 +296,9 @@ func (d *dispatcher) handle(ctx context.Context, env api.Envelope, tx wsclient.S
 		}
 		go d.handleTreeList(ctx, env.ID, p, tx)
 
+	case api.MsgSnapshotsRefresh:
+		go d.refreshSnapshots(ctx, tx)
+
 	case api.MsgScheduleSet:
 		var p api.ScheduleSetPayload
 		if err := env.UnmarshalPayload(&p); err != nil {
@@ -405,6 +408,22 @@ func (d *dispatcher) handle(ctx context.Context, env api.Envelope, tx wsclient.S
 	return nil
 }
 
+func (d *dispatcher) refreshSnapshots(ctx context.Context, tx wsclient.Sender) {
+	creds, err := d.secrets.Load()
+	if err != nil || creds.Empty() {
+		slog.Warn("ws agent: snapshots.refresh unavailable", "err", err)
+		return
+	}
+	r := runner.New(runner.Config{
+		ResticBin: d.resticBin, ResticVersion: d.resticVer,
+		RepoURL: creds.URL, RepoUsername: creds.Username, RepoPassword: creds.Password,
+		SupportsRestoreNoOwnership: d.resticSupportsNoOwnership,
+	}, tx, time.Second)
+	if err := r.RefreshSnapshots(ctx); err != nil {
+		slog.Warn("ws agent: snapshots.refresh failed", "err", err)
+	}
+}
+
 // handleTreeList runs `restic ls --json <snapshot> <path>` and ships
 // the matching tree.list.result envelope back, correlated by the
 // request envelope's ID. Errors (missing creds, restic failure)