feat: add prescription refills column to planner table and email (#207)

- Add 6th column 'Prescription refills' to frontend Planner table
- Add matching column to backend planner email (HTML + plaintext)
- Show remaining refills for meds with prescription tracking, '–' otherwise
- Add backend translations for new column header (EN + DE)
- Add frontend i18n keys for prescription refills column
- Update planner tests with medications table schema

Closes #203

frontend/src/i18n/de.json

@@ -207,6 +207,7 @@
       "medication": "Medikament",
       "usage": "Verbrauch",
       "blistersNeeded": "Blister benötigt",
+      "prescriptionRefills": "Rezept-Nachfüllungen",
       "blisters": "Blister",
       "available": "Verfügbar"
     }

frontend/src/i18n/en.json

@@ -207,6 +207,7 @@
       "medication": "Medication",
       "usage": "Usage",
       "blistersNeeded": "Blisters needed",
+      "prescriptionRefills": "Prescription refills",
       "blisters": "Blisters",
       "available": "Available"
     }

frontend/src/pages/PlannerPage.tsx

@@ -196,16 +196,19 @@ export function PlannerPage() {
 				</form>
 				{plannerRows.length > 0 && (
 					<>
-						<div className="table">
+						<div className="table table-6">
 							<div className="table-head">
 								<span>{t("planner.table.medication")}</span>
 								<span>{t("planner.table.usage")}</span>
 								<span>{t("planner.table.blistersNeeded")}</span>
+								<span>{t("planner.table.prescriptionRefills")}</span>
 								<span>{t("planner.table.available")}</span>
 								<span>{t("table.status")}</span>
 							</div>
 							{plannerRows.map((row) => {
-								const med = meds.find((m) => m.name === row.medicationName);
+								const med =
+									meds.find((m) => m.id === row.medicationId) || meds.find((m) => m.name === row.medicationName);
+								const remainingRefills = med?.prescriptionEnabled ? (med.prescriptionRemainingRefills ?? 0) : null;
 								return (
 									<div key={row.medicationId} className="table-row clickable" onClick={() => med && openMedDetail(med)}>
 										<span data-label={t("planner.table.medication")} className="cell-with-avatar">
@@ -219,6 +222,7 @@ export function PlannerPage() {
 										<span data-label={t("planner.table.blisters")}>
 											{row.packageType === "bottle" ? "–" : `${row.blistersNeeded} × ${row.blisterSize}`}
 										</span>
+										<span data-label={t("planner.table.prescriptionRefills")}>{remainingRefills ?? "–"}</span>
 										<span data-label={t("planner.table.available")}>
 											{row.packageType === "bottle" ? (
 												`${Math.round(row.loosePills * 10) / 10} ${Math.round(row.loosePills * 10) / 10 === 1 ? t("common.pill") : t("common.pills")}`