Fix: Energie-Dashboard Nodes größer (R=56), Labels aus API, Abrechnungsperiode konfig. (v1.7.1)

- SVG-Nodes: Radius 44 → 56, Icon 22 → 26px, Abstände neu berechnet
- Segment-Pfade an neue Positionen angepasst (40px Abstand Kante→Kante)
- period.monthly.label / yearly.label statt hardcoded "Diesen Monat" / "Dieses Jahr"
- billing_day/billing_month: history.period_key(), /api/period-energy, Settings-UI

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

haos-addon/src/history.py

@@ -52,10 +52,22 @@ def init_db():
     log.info("History DB initialisiert: %s", DB_PATH)
 
 
-def period_key(period_type: str) -> str:
+def period_key(period_type: str, billing_day: int = 1, billing_month: int = 1) -> str:
     import datetime
-    now = datetime.date.today()
-    return now.strftime("%Y-%m") if period_type == "monthly" else now.strftime("%Y")
+    today = datetime.date.today()
+    if period_type == "monthly":
+        return today.strftime("%Y-%m")
+    # Jahresperiode: Beginn = letzter Abrechnungsstichtag
+    try:
+        start = datetime.date(today.year, billing_month, billing_day)
+    except ValueError:
+        start = datetime.date(today.year, billing_month, 1)
+    if today < start:
+        try:
+            start = datetime.date(today.year - 1, billing_month, billing_day)
+        except ValueError:
+            start = datetime.date(today.year - 1, billing_month, 1)
+    return start.isoformat()  # z.B. "2025-04-01"
 
 
 def save_period_start_if_new(agg_id: str, period_type: str, key: str, current_value: float):