feat(ui): distinguish cancel-from-hold as "Failed (cancelled)"

Before, a run that failed, held for operator review, and was then
cancelled showed up on the tile and run header as plain "Cancelled"
with an idle-grey mood — indistinguishable from a mid-stage cancel of
a healthy run. That hides the actual failure from the dashboard.

Now: when State=Cancelled with FailedStage still set (the hold-cancel
signature the heartbeat handler already uses to pick reboot vs
cancel_stage), the badge reads "Failed (cancelled)" with a fail-
colored mood. Mid-stage cancels keep reading as plain "Cancelled".

internal/web/templates/host_tile_test.go

@@ -131,6 +131,48 @@ func TestHostTile_NoStageStrip(t *testing.T) {
 	}
 }
 
+// TestTileStatusCancelledFromHold: a run that entered FailedHolding and
+// was later Cancelled by the operator should read as a failure, not a
+// plain cancel. The discriminator is FailedStage being set — mid-stage
+// cancels leave it empty.
+func TestTileStatusCancelledFromHold(t *testing.T) {
+	cases := []struct {
+		name       string
+		run        *model.Run
+		wantStatus string
+		wantMood   string
+	}{
+		{
+			name:       "cancelled from hold shows failed",
+			run:        &model.Run{State: model.StateCancelled, FailedStage: "Storage"},
+			wantStatus: "Failed (cancelled)",
+			wantMood:   "fail",
+		},
+		{
+			name:       "mid-stage cancel stays plain cancelled",
+			run:        &model.Run{State: model.StateCancelled},
+			wantStatus: "Cancelled",
+			wantMood:   "idle",
+		},
+		{
+			name:       "failed-holding itself still reads as FailedHolding",
+			run:        &model.Run{State: model.StateFailedHolding, FailedStage: "Storage"},
+			wantStatus: string(model.StateFailedHolding),
+			wantMood:   "fail",
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := tileStatus(tc.run); got != tc.wantStatus {
+				t.Errorf("tileStatus = %q, want %q", got, tc.wantStatus)
+			}
+			if got := tileMood(tc.run); got != tc.wantMood {
+				t.Errorf("tileMood = %q, want %q", got, tc.wantMood)
+			}
+		})
+	}
+}
+
 func TestLastSeenLabelAndClass(t *testing.T) {
 	if got := lastSeenLabel(nil); got != "never" {
 		t.Fatalf("label nil = %q, want never", got)