Fix SSH tunnel Docker build for Dokploy deployment

Changes:
- Fix Dockerfile COPY path from ../secrets to secrets/ (Docker doesn't allow parent directory access)
- Create ssh-tunnel/secrets/ directory structure with comprehensive README
- Add .dockerignore for ssh-tunnel to optimize build context
- Add DOKPLOY_DEPLOYMENT.md with complete deployment guide including:
  * SSH key configuration options (repository, secrets manager, BuildKit)
  * Environment variables setup
  * Step-by-step deployment instructions
  * Troubleshooting section
  * Security best practices
- Update .gitignore to allow secrets/README.md files for documentation

This resolves the Dokploy build failure: "failed to calculate checksum of ref... /secrets/roa_oracle_server: not found"

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

ssh-tunnel/.dockerignore

@@ -0,0 +1,68 @@
+# SSH Tunnel Docker Build - Ignore Patterns
+
+# Documentation (not needed in container)
+README_SSH_KEY.md
+docs/
+*.md
+!secrets/README.md
+
+# Git files
+.git/
+.gitignore
+.gitattributes
+
+# Development and test files
+*.test
+*.tmp
+*.temp
+*.log
+*.bak
+*.swp
+*.swo
+*~
+
+# IDE files
+.vscode/
+.idea/
+*.sublime-*
+
+# SSH files that should NOT be in the image
+# (only roa_oracle_server should be copied)
+secrets/*_test*
+secrets/*.pub
+secrets/*.pem
+secrets/*.key
+secrets/known_hosts
+secrets/config
+
+# Backup files
+*.backup
+*.orig
+*.old
+
+# OS files
+.DS_Store
+Thumbs.db
+._*
+
+# Python cache (if any scripts generate them)
+__pycache__/
+*.pyc
+*.pyo
+*.pyd
+.Python
+
+# Temporary files
+temp/
+tmp/
+*.pid
+
+# Build artifacts
+*.tar
+*.tar.gz
+*.zip
+
+# Keep only what's needed for the build:
+# - Dockerfile (implicit)
+# - ssh_tunnel_docker.sh
+# - secrets/roa_oracle_server