fix(server): handle collapsed row panels and deduplicate metric list in tests

Walk nested panels inside collapsed row panels so the dashboard coverage
test does not silently miss metrics when a re-exported JSON uses Grafana's
collapsed row format.

Reuse knownSortieMetrics in TestNewPromMetrics to eliminate the duplicated
metric list and prevent drift between the two tests.

Author: serghei-dev

internal/server/grafana_coverage_test.go

@@ -63,26 +63,34 @@ func TestGrafanaDashboardCoversAllMetrics(t *testing.T) {
 		t.Fatalf("reading grafana dashboard: %v", err)
 	}
 
+	type panelJSON struct {
+		Targets []struct {
+			Expr string `json:"expr"`
+		} `json:"targets"`
+		Panels []panelJSON `json:"panels"` // collapsed rows nest panels here
+	}
 	var dash struct {
-		Panels []struct {
-			Targets []struct {
-				Expr string `json:"expr"`
-			} `json:"targets"`
-		} `json:"panels"`
+		Panels []panelJSON `json:"panels"`
 	}
 	if err := json.Unmarshal(raw, &dash); err != nil {
 		t.Fatalf("parsing grafana dashboard JSON: %v", err)
 	}
 
-	// Collect all sortie_ base metric names referenced across all panels.
+	// Collect all sortie_ base metric names referenced across all panels,
+	// including panels nested inside collapsed rows.
 	referenced := make(map[string]bool, len(knownSortieMetrics))
-	for _, panel := range dash.Panels {
-		for _, target := range panel.Targets {
-			for _, match := range promqlMetricRE.FindAllString(target.Expr, -1) {
-				referenced[stripHistogramSuffix(match)] = true
+	var walkPanels func([]panelJSON)
+	walkPanels = func(panels []panelJSON) {
+		for _, panel := range panels {
+			for _, target := range panel.Targets {
+				for _, match := range promqlMetricRE.FindAllString(target.Expr, -1) {
+					referenced[stripHistogramSuffix(match)] = true
+				}
 			}
+			walkPanels(panel.Panels)
 		}
 	}
+	walkPanels(dash.Panels)
 
 	for _, name := range knownSortieMetrics {
 		if !referenced[name] {

internal/server/metrics_test.go

@@ -134,32 +134,7 @@ func TestNewPromMetrics(t *testing.T) {
 
 	families := gatherFamilies(t, m)
 
-	sortieMetrics := []string{
-		"sortie_sessions_running",
-		"sortie_sessions_retrying",
-		"sortie_slots_available",
-		"sortie_active_sessions_elapsed_seconds",
-		"sortie_tokens_total",
-		"sortie_agent_runtime_seconds_total",
-		"sortie_dispatches_total",
-		"sortie_worker_exits_total",
-		"sortie_retries_total",
-		"sortie_reconciliation_actions_total",
-		"sortie_poll_cycles_total",
-		"sortie_tracker_requests_total",
-		"sortie_handoff_transitions_total",
-		"sortie_dispatch_transitions_total",
-		"sortie_tracker_comments_total",
-		"sortie_tool_calls_total",
-		"sortie_poll_duration_seconds",
-		"sortie_worker_duration_seconds",
-		"sortie_ssh_host_usage",
-		"sortie_ci_status_checks_total",
-		"sortie_ci_escalations_total",
-		"sortie_build_info",
-	}
-
-	for _, name := range sortieMetrics {
+	for _, name := range knownSortieMetrics {
 		if _, ok := families[name]; !ok {
 			t.Errorf("expected metric family %q not found", name)
 		}