FE-3 + FE-4: Full-Featured Research-Ansicht + Docker Deployment

FE-3:
- Error-System: ErrorBannerStore + ErrorBanner (stapelbar, auto-hide, 5 categories)
- ContradictionBanner: Visuelle Widerspruchserkennung
- StatusTab: Zeitleiste, Fortschrittsbalken, Details
- ShareButton: Inline-Share mit Geteilt-Badge
- ShareModal: Ablaufzeit (24h-30Tage/Nie), Max-Views, Copy/Revoke
- research/{id}/+page.svelte: 6 Tabs mit Polling (5s), onDestroy cleanup
- share/[token]/+page.svelte: Vollständige Read-Only Share-Ansicht mit Wasserzeichen
- research/new/+page.svelte: Char-Counter, Language/Depth-Auswahl

FE-4:
- Dockerfile: HEALTHCHECK, Error-Handling, multi-stage build
- Caddyfile: HTTPS, Security Headers, gzip+zstd
- docker-compose.yml: Healthchecks, resource limits, restart policy
- tests/: Theme, API, Formatter, Share-Link Tests
- README.md: Architektur-Diagramm, Installation, Nutzung
- CHANGELOG.md: FE-0 bis FE-4

Dockerfile

@@ -1,23 +1,33 @@
 # Build stage
 FROM node:22-alpine AS builder
 WORKDIR /app
-COPY package.json .
+
+# Copy package files
+COPY package.json ./
+COPY package-lock.json ./
 RUN npm ci
+
+# Copy source and build
 COPY . .
 ENV NODE_ENV=production
-RUN npm run build
+RUN npm run build || exit 1
 
 # Production stage
 FROM node:22-alpine AS runtime
 WORKDIR /app
+
+# Copy built assets and dependencies
 COPY --from=builder /app/build ./build
 COPY --from=builder /app/node_modules ./node_modules
-COPY package.json package.json
+COPY package.json .
 
 # Non-root user
 RUN addgroup -S nsct && adduser -S nsct -G nsct
 USER nsct
 
+# Health check
+HEALTHCHECK --interval=30s --timeout=3s --start-period=10s --retries=3 CMD wget -qO- http://localhost:3000/health || exit 1
+
 EXPOSE 3000
 ENV HOST=0.0.0.0
 ENV PORT=3000