feat: publish durable queue and spool gauges

internal/client/spool/telemetry_test.go

@@ -0,0 +1,22 @@
+package spool
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestTelemetryReportsQueuedDurableSpool_HP_OPS_07(t *testing.T) {
+	t.Parallel()
+	ctx := context.Background()
+	store := openTestStore(t, ctx, filepath.Join(t.TempDir(), "spool"), DefaultTombstoneLimit)
+	issue := testUUID(t, "019c46f1-1d02-7000-8000-0000000000d2")
+	if _, err := store.AcceptCommand(ctx, testCommand(issue, []byte("telemetry")), time.Now().UTC()); err != nil {
+		t.Fatal(err)
+	}
+	telemetry, err := store.Telemetry(ctx)
+	if err != nil || telemetry.QueuedCommands != 1 || telemetry.ChargedBytes == 0 {
+		t.Fatalf("telemetry = %#v, %v", telemetry, err)
+	}
+}