feat: add OWM alerts, UV index support, and provider info UI

- Parse OWM One Call 3.0 weather alerts and map to Warning structs
- Map hourly UVI from OWM response to HourlyForecast.UVIndex
- Add severity helper mapping OWM alert tags to severity levels
- Extract UVIndex through compute layer to timeline slots
- Smart warnings: use provider-supplied alerts, fall back to DWD
- Show UV index in dashboard timeline tooltips
- Add provider description below forecast dropdown with i18n

web/js/dashboard.js

@@ -689,9 +689,10 @@
         const idx = parseInt(cell.dataset.idx);
         const slot = timeline[idx];
         const modeLabel = labels[slot.coolMode] || slot.coolMode || "";
+        const uviStr = slot.uvIndex ? ` \u00b7 UV ${slot.uvIndex.toFixed(1)}` : "";
         let tooltipHtml = `
           <div class="font-medium mb-1">${slot.hourStr}</div>
-          <div>${slot.tempC.toFixed(1)}\u00b0C \u00b7 ${(slot.humidityPct || 0).toFixed(0)}% RH${slot.pressureHpa ? ` \u00b7 ${slot.pressureHpa.toFixed(0)} hPa` : ""}</div>
+          <div>${slot.tempC.toFixed(1)}\u00b0C \u00b7 ${(slot.humidityPct || 0).toFixed(0)}% RH${slot.pressureHpa ? ` \u00b7 ${slot.pressureHpa.toFixed(0)} hPa` : ""}${uviStr}</div>
           <div class="capitalize">${slot.budgetStatus} \u00b7 ${esc(modeLabel)}</div>
         `;
         const hourActions = _hourActionMap && _hourActionMap[slot.hour];

web/js/db.js

@@ -255,34 +255,53 @@ async function fetchForecastForProfile(profileId) {
       sunshineMin: h.SunshineMin ?? h.sunshineMin ?? null,
       apparentTempC: h.ApparentTempC ?? h.apparentTempC ?? null,
       pressureHpa: h.PressureHpa ?? h.pressureHpa ?? null,
+      uvIndex: h.UVIndex ?? h.uvIndex ?? null,
     });
   }
 
-  // Fetch warnings (optional — don't fail if this errors)
+  // Warnings: use provider-supplied warnings if available, otherwise fall back to DWD
   let warningCount = 0;
-  try {
-    const wResp = await fetch("/api/weather/warnings", {
-      method: "POST",
-      headers: { "Content-Type": "application/json" },
-      body: JSON.stringify({ lat: profile.latitude, lon: profile.longitude }),
-    });
-    if (wResp.ok) {
-      const wData = await wResp.json();
-      await deleteByIndex("warnings", "profileId", profileId);
-      for (const w of (wData.warnings || [])) {
-        await dbAdd("warnings", {
-          profileId,
-          headline: w.Headline || w.headline || "",
-          severity: w.Severity || w.severity || "",
-          description: w.Description || w.description || "",
-          instruction: w.Instruction || w.instruction || "",
-          onset: w.Onset || w.onset || "",
-          expires: w.Expires || w.expires || "",
-        });
-        warningCount++;
-      }
+  const providerWarnings = data.Warnings || data.warnings || [];
+  if (providerWarnings.length > 0) {
+    await deleteByIndex("warnings", "profileId", profileId);
+    for (const w of providerWarnings) {
+      await dbAdd("warnings", {
+        profileId,
+        headline: w.Headline || w.headline || "",
+        severity: w.Severity || w.severity || "",
+        description: w.Description || w.description || "",
+        instruction: w.Instruction || w.instruction || "",
+        onset: w.Onset || w.onset || "",
+        expires: w.Expires || w.expires || "",
+      });
+      warningCount++;
     }
-  } catch (_) { /* warnings are optional */ }
+  } else {
+    // Fall back to DWD warnings (optional — don't fail if this errors)
+    try {
+      const wResp = await fetch("/api/weather/warnings", {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ lat: profile.latitude, lon: profile.longitude }),
+      });
+      if (wResp.ok) {
+        const wData = await wResp.json();
+        await deleteByIndex("warnings", "profileId", profileId);
+        for (const w of (wData.warnings || [])) {
+          await dbAdd("warnings", {
+            profileId,
+            headline: w.Headline || w.headline || "",
+            severity: w.Severity || w.severity || "",
+            description: w.Description || w.description || "",
+            instruction: w.Instruction || w.instruction || "",
+            onset: w.Onset || w.onset || "",
+            expires: w.Expires || w.expires || "",
+          });
+          warningCount++;
+        }
+      }
+    } catch (_) { /* warnings are optional */ }
+  }
 
   await setSetting("lastFetched", new Date().toISOString());
   return { forecasts: hourly.length, warnings: warningCount };
@@ -416,6 +435,7 @@ async function getComputePayload(profileId, dateStr) {
       sunshineMin: f.sunshineMin ?? null,
       apparentTempC: f.apparentTempC ?? null,
       pressureHpa: f.pressureHpa ?? null,
+      uvIndex: f.uvIndex ?? null,
     })),
     warnings: warnings.map(w => ({
       headline: w.headline || "",

web/js/setup.js

@@ -995,13 +995,19 @@
   function toggleForecastApiKeyField(provider) {
     const group = document.getElementById("forecast-apikey-group");
     const hint = document.getElementById("forecast-provider-hint");
+    const desc = document.getElementById("forecast-provider-desc");
+    const ts = window.HG && window.HG.t ? window.HG.t : {};
+    const providerDesc = (ts.setup && ts.setup.forecast && ts.setup.forecast.providerDesc) || {};
     if (provider === "openweathermap") {
       group.classList.remove("hidden");
       hint.innerHTML = '<a href="https://openweathermap.org/api/one-call-3" target="_blank" rel="noopener" class="text-orange-600 hover:underline">Requires One Call 3.0 subscription \u2192</a>';
+      if (desc) desc.textContent = providerDesc.openweathermap || "48h hourly + 8-day daily forecast. Includes UV index and worldwide weather alerts.";
     } else {
       group.classList.add("hidden");
       hint.textContent = "";
+      if (desc) desc.textContent = providerDesc.openmeteo || "Free, no API key needed. 3-day hourly forecast (temp, humidity, wind, solar, pressure). Warnings via DWD (Germany only).";
     }
+    if (desc) desc.classList.remove("hidden");
   }
 
   document.getElementById("forecast-provider-select").addEventListener("change", (e) => {