fix(targets): label the systolic bar on the blood-pressure target card

The card stacks two range bars for blood pressure. The diastolic bar
carried its label; the systolic one had none and no key to render, so the
pair read as one unnamed bar above a "Diastolic" one. Both bars now name
their reading (new key targets.systolic in every locale).

messages/de.json

@@ -8901,6 +8901,7 @@
     "inTarget": "Im Zielbereich",
     "aboveTarget": "{delta} {unit} über Zielbereich",
     "belowTarget": "{delta} {unit} unter Zielbereich",
+    "systolic": "Systolisch",
     "diastolic": "Diastolisch",
     "glucoseFasting": "Glukose, nüchtern",
     "glucosePostprandial": "Glukose, postprandial",