docs: add HTTPS production deployment guide with nginx reverse proxy

[cfsmp3]

Summary

• Add example frontend environment file (example.frontend.env)
• Add nginx reverse proxy configuration for HTTPS deployment (example.nginx.conf)
• Update production README with comprehensive HTTPS deployment guide

Changes

New Files

• production/example.frontend.env: Example frontend environment variables for HTTPS deployment
• production/example.nginx.conf: Complete nginx configuration with:
  • HTTP to HTTPS redirect
  • SSL termination using Let's Encrypt certificates
  • Proxy rules for all backend API routes (/auth/, /api/, /tasks, etc.)
  • WebSocket support for /ws endpoint
  • SSL termination for taskchampion sync server on port 8080

Updated Files

• production/README.md: Reorganized into three deployment options:
  1. Docker (HTTP only, for local/development)
  2. Docker with nginx reverse proxy (HTTPS, recommended for production)
  3. Kubernetes

Why

Google OAuth requires HTTPS redirect URIs for production deployments (HTTP is only allowed for localhost). This guide provides a complete, tested configuration for deploying CCSync with proper SSL support.

Test plan

• Configuration tested on fresh Ubuntu 24.04 VPS
• SSL certificates obtained via Let's Encrypt
• All services (frontend, backend, syncserver) accessible via HTTPS
• OAuth flow working with HTTPS redirect URI

🤖 Generated with Claude Code

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