frontend: fix Analysis chart overflow + gate the Live card

- Live card no longer streams on mount: a "Go live"/"Pause" toggle starts/stops
  the 1s simulation, so the page stays idle by default (perf). Widen the live
  chart's left margin so the y-axis values sit inside the card.
- Weekly-appointments bar chart: drop the misused <BarYAxis>, which printed the
  weekday categories down the left and overflowed the card (vertical bars only
  need the x-axis).
- Patient-growth area chart: one x tick per month so every point is labelled.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/lib/i18n/locales/en/translation.json

@@ -556,7 +556,10 @@
     "live": {
       "title": "Live",
       "subtitle": "Patients currently in the building, updating in real time.",
-      "label": "In the building now"
+      "label": "In the building now",
+      "start": "Go live",
+      "pause": "Pause",
+      "idle": "Live stream paused — press Go live to start."
     },
     "patientVolume": {
       "title": "Patient volume",