Forecasting app: hybrid port to HNF stack

Python FastAPI ML backend kept intact; auth replaced with central hnf_session cookie verification. Frontend rebuilt on React 18 + TS + Vite with stack design system, Plotly charts retained. Shared Postgres via DATABASE_URL; schema applied on startup.

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

frontend/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "forecasting-frontend",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc && vite build",
+    "preview": "vite preview"
+  },
+  "dependencies": {
+    "@tanstack/react-query": "^5.32.0",
+    "axios": "^1.6.8",
+    "lucide-react": "^0.395.0",
+    "plotly.js": "^2.29.0",
+    "react": "^18.3.1",
+    "react-dom": "^18.3.1",
+    "react-plotly.js": "^2.6.0",
+    "react-router-dom": "^6.22.0"
+  },
+  "devDependencies": {
+    "@types/plotly.js": "^2.12.29",
+    "@types/react": "^18.3.1",
+    "@types/react-dom": "^18.3.0",
+    "@types/react-plotly.js": "^2.6.4",
+    "@vitejs/plugin-react": "^4.2.1",
+    "typescript": "^5.4.5",
+    "vite": "^5.2.11"
+  }
+}