refactor: complete rewrite as React+FastAPI dashboard

Replace monolithic Jinja2 template with modern stack:

Backend (FastAPI):
- Modular router/service architecture
- Async PostgreSQL (asyncpg) for news from n8n pipeline
- Live Unraid server stats (2 servers via API)
- Home Assistant, Vikunja tasks, weather (wttr.in)
- WebSocket broadcast for real-time updates (15s)
- TTL cache per endpoint, all config via ENV vars

Frontend (React + Vite + TypeScript):
- Glassmorphism dark theme with Tailwind CSS
- Responsive grid: mobile/tablet/desktop/ultrawide
- Weather cards, hourly forecast, news with category tabs
- Server stats (CPU ring, RAM bar, Docker list)
- Home Assistant controls, task management
- Live clock, WebSocket connection indicator

Infrastructure:
- Multi-stage Dockerfile (node:22-alpine + python:3.11-slim)
- docker-compose with full ENV configuration
- Kaniko CI/CD pipeline for GitLab registry

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

Dockerfile

@@ -1,23 +1,21 @@
-FROM python:3.11-slim
+# Stage 1: Build React Frontend
+FROM node:22-alpine AS frontend
+WORKDIR /app/web
+COPY web/package*.json ./
+RUN npm ci
+COPY web/ ./
+RUN npm run build
 
+# Stage 2: Python Backend + Static Files
+FROM python:3.11-slim
 WORKDIR /app
 
-# Install dependencies
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt
 
-# Copy application
-COPY src/ ./src/
-COPY templates/ ./templates/
-COPY static/ ./static/
-
-# Environment variables (will be overridden at runtime)
-ENV VIKUNJA_URL=http://10.10.10.10:3456/api/v1
-ENV VIKUNJA_TOKEN=""
-ENV HA_URL=https://homeassistant.daddelolymp.de
-ENV HA_TOKEN=""
-ENV WEATHER_LOCATION=Leverkusen
+COPY server/ ./server/
+COPY --from=frontend /app/web/dist ./static/
 
 EXPOSE 8080
 
-CMD ["uvicorn", "src.main:app", "--host", "0.0.0.0", "--port", "8080"]
+CMD ["uvicorn", "server.main:app", "--host", "0.0.0.0", "--port", "8080"]