monitoring: Wetter-Tagesberichte in Grafana auffindbar machen

- weather-report-history.json (ha-weather-report-history): Finder-Tabelle,
  eine Zeile pro Tag (Datum, Kurzbewertung, T min/max/Mittel, Regen, UV, Boee)
  mit Drilldown-Data-Link aufs Tagesbericht-Dashboard
- weather-day-report.json: Zeitzone Europe/Berlin, Info-Panel zur Tagesauswahl,
  Nav-Dropdown zu den Wetter-Dashboards
- monitoring/README: Abschnitt Wetter-Tagesberichte (finden, Datum waehlen,
  Quelle InfluxDB-SQL statt Markdown-Index, Deploy, Explore-Test)

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

monitoring/grafana/dashboards/weather-day-report.json

@@ -2,19 +2,32 @@
   "uid": "ha-weather-day-report",
   "title": "Wetterbericht KalliHome",
   "tags": ["weather", "ecowitt", "homeassistant", "report"],
-  "timezone": "browser",
+  "timezone": "Europe/Berlin",
   "schemaVersion": 39,
-  "version": 1,
+  "version": 2,
   "refresh": "",
   "time": { "from": "now-1d/d", "to": "now/d" },
   "templating": { "list": [] },
   "annotations": { "list": [] },
+  "links": [
+    { "asDropdown": true, "icon": "external link", "includeVars": false, "keepTime": false, "tags": ["weather"], "targetBlank": false, "title": "Wetter-Dashboards", "tooltip": "", "type": "dashboards", "url": "" }
+  ],
   "panels": [
+    {
+      "id": 2,
+      "title": "",
+      "type": "text",
+      "gridPos": { "h": 4, "w": 24, "x": 0, "y": 0 },
+      "options": {
+        "mode": "markdown",
+        "content": "## Tag auswählen\n\n**Standard:** gestern (ganzer Tag, Europe/Berlin).\n\n**Anderen Tag:** Zeitbereich oben rechts → *Absolute time range* → z. B. From `2026-06-15 00:00:00`, To `2026-06-16 00:00:00` → **Apply** (Zeiten gelten in Europe/Berlin).\n\n**Alle Tage als Liste:** [Wetter-Tagesberichte](/d/ha-weather-report-history) – dort jeden Tag per Klick öffnen."
+      }
+    },
     {
       "id": 1,
       "title": "Tagesbericht",
       "type": "table",
-      "gridPos": { "h": 16, "w": 24, "x": 0, "y": 0 },
+      "gridPos": { "h": 16, "w": 24, "x": 0, "y": 4 },
       "datasource": { "type": "influxdb", "uid": "ha-weather-influx" },
       "fieldConfig": {
         "defaults": {