Feature: Abrechnungsperiode + Strompreise im Energie-Dashboard (v1.7.0)

- history.py: Tabelle period_starts — speichert kWh-Zählerstand zu Monats-/Jahresbeginn
- main.py: price_import/price_export in Config; /api/period-energy Endpoint
- Web UI: Preisfelder in Einstellungen (€/kWh Bezug + Vergütung)
- Energie-Dashboard: Cards zeigen Monat/Jahr kWh + Kosten statt All-Time-Total

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

haos-addon/src/main.py

@@ -86,6 +86,8 @@ def _defaults() -> Dict[str, Any]:
         "mqtt_port": 1883,
         "mqtt_user": "",
         "mqtt_pass": "",
+        "price_import": 0.30,
+        "price_export": 0.08,
         "inverters": [],
     }
 
@@ -114,6 +116,8 @@ def save_config():
         "mqtt_port": State.mqtt_cfg.get("mqtt_port", 1883),
         "mqtt_user": State.mqtt_cfg.get("mqtt_user", ""),
         "mqtt_pass": State.mqtt_cfg.get("mqtt_pass", ""),
+        "price_import": State.mqtt_cfg.get("price_import", 0.30),
+        "price_export": State.mqtt_cfg.get("price_export", 0.08),
         "inverters": State.inverters_cfg,
     }
     with open(CONFIG_PATH, "w") as f:
@@ -338,10 +342,41 @@ def api_save_config():
                 State.mqtt_cfg[k] = data[k]
         if data.get("mqtt_pass"):
             State.mqtt_cfg["mqtt_pass"] = data["mqtt_pass"]
+        for k in ("price_import", "price_export"):
+            if k in data:
+                State.mqtt_cfg[k] = float(data[k])
         save_config()
     threading.Thread(target=_restart_all, daemon=True).start()
     return jsonify({"ok": True})
 
+
+@app.get("/api/period-energy")
+def api_period_energy():
+    agg = _compute_aggregates()
+    price_import = float(State.mqtt_cfg.get("price_import", 0.30))
+    price_export = float(State.mqtt_cfg.get("price_export", 0.08))
+
+    result = {"price_import": price_import, "price_export": price_export}
+
+    for period_type in ("monthly", "yearly"):
+        key = history.period_key(period_type)
+        entry = {}
+        for agg_id in ("grid_import_kwh", "grid_export_kwh", "total_energy_today"):
+            cur = agg.get(agg_id)
+            if cur is None:
+                continue
+            history.save_period_start_if_new(agg_id, period_type, key, cur)
+            val = history.get_period_consumption(agg_id, period_type, key, cur)
+            if val is not None:
+                entry[agg_id] = round(val, 2)
+        if "grid_import_kwh" in entry:
+            entry["import_cost"] = round(entry["grid_import_kwh"] * price_import, 2)
+        if "grid_export_kwh" in entry:
+            entry["export_revenue"] = round(entry["grid_export_kwh"] * price_export, 2)
+        result[period_type] = entry
+
+    return jsonify(result)
+
 @app.get("/api/inverters-config")
 def api_get_inverters():
     with State.lock: