feat: Punkte-Reveal with confetti animation

Shows animated reveal overlay for unseen match results.
Exact match (3pts) triggers confetti explosion.
Each reveal shown only once (localStorage tracking).

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

frontend/package-lock.json

@@ -8,12 +8,14 @@
       "name": "wm2026-tippspiel-frontend",
       "version": "1.0.0",
       "dependencies": {
+        "canvas-confetti": "^1.9.4",
         "lucide-react": "^1.7.0",
         "react": "^18.3.1",
         "react-dom": "^18.3.1",
         "react-router-dom": "^6.24.0"
       },
       "devDependencies": {
+        "@types/canvas-confetti": "^1.9.0",
         "@types/react": "^18.3.3",
         "@types/react-dom": "^18.3.0",
         "@vitejs/plugin-react": "^4.3.1",
@@ -1155,6 +1157,13 @@
         "@babel/types": "^7.28.2"
       }
     },
+    "node_modules/@types/canvas-confetti": {
+      "version": "1.9.0",
+      "resolved": "https://registry.npmjs.org/@types/canvas-confetti/-/canvas-confetti-1.9.0.tgz",
+      "integrity": "sha512-aBGj/dULrimR1XDZLtG9JwxX1b4HPRF6CX9Yfwh3NvstZEm1ZL7RBnel4keCPSqs1ANRu1u2Aoz9R+VmtjYuTg==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/estree": {
       "version": "1.0.8",
       "resolved": "https://registry.npmjs.org/@types/estree/-/estree-1.0.8.tgz",
@@ -1279,6 +1288,16 @@
       ],
       "license": "CC-BY-4.0"
     },
+    "node_modules/canvas-confetti": {
+      "version": "1.9.4",
+      "resolved": "https://registry.npmjs.org/canvas-confetti/-/canvas-confetti-1.9.4.tgz",
+      "integrity": "sha512-yxQbJkAVrFXWNbTUjPqjF7G+g6pDotOUHGbkZq2NELZUMDpiJ85rIEazVb8GTaAptNW2miJAXbs1BtioA251Pw==",
+      "license": "ISC",
+      "funding": {
+        "type": "donate",
+        "url": "https://www.paypal.me/kirilvatev"
+      }
+    },
     "node_modules/convert-source-map": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-2.0.0.tgz",