feat(alerts): zehn Warnregeln mit Worker, Liste und Einstellungen (#011)

Regeln als reine Funktionen, Abgleich oeffnet und schliesst Warnungen anhand
eines Fingerabdrucks. Worker wertet stuendlich aus, zusaetzlich nach jedem
Report. 123 Tests.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

package-lock.json

@@ -16,6 +16,7 @@
         "admin-lte": "^4.9.1",
         "bootstrap": "^5.3.8",
         "bootstrap-icons": "^1.13.1",
+        "croner": "^10.0.1",
         "next": "16.3.5",
         "react": "19.2.8",
         "react-dom": "19.2.8",
@@ -4788,6 +4789,25 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/croner": {
+      "version": "10.0.1",
+      "resolved": "https://registry.npmjs.org/croner/-/croner-10.0.1.tgz",
+      "integrity": "sha512-ixNtAJndqh173VQ4KodSdJEI6nuioBWI0V1ITNKhZZsO0pEMoDxz539T4FTTbSZ/xIOSuDnzxLVRqBVSvPNE2g==",
+      "funding": [
+        {
+          "type": "other",
+          "url": "https://paypal.me/hexagonpp"
+        },
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/hexagon"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=18.0"
+      }
+    },
     "node_modules/cross-spawn": {
       "version": "7.0.6",
       "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.6.tgz",