Fix Docker deployment by adding missing Dockerfile and resolving configuration issues

[Copilot]

This PR resolves the "firewall blocking" issue that was preventing the API service from being accessible in containerized environments. The root cause was missing Docker infrastructure that made it appear as if network access was blocked.

Problem

The docker-compose.yml file referenced a non-existent Dockerfile (services/api/Dockerfile), which caused:

• Docker build failures when attempting to deploy the stack
• API service being inaccessible on port 3000 in containerized environments
• The appearance of "firewall blocking" when the service simply wasn't running

Additional issues included:

• Broken workspace configuration referencing non-existent directories
• Incompatible dependency features in tower-http
• Missing .gitignore causing build artifacts to be committed

Solution

Added Production-Ready Dockerfile

Created services/api/Dockerfile with:

• Multi-stage build for optimal image size (build dependencies separate from runtime)
• Security best practices using non-root user (appuser)
• Integrated health checks leveraging the existing /health endpoint
• Dependency caching for faster subsequent builds
• Minimal runtime image based on Debian Bookworm Slim

Fixed Configuration Issues

• Workspace cleanup: Removed references to non-existent apps/*, packages/*, and trainer directories
• Dependency fix: Updated tower-http features from compression to compression-br and compression-gzip
• Docker Compose modernization: Removed obsolete version field to eliminate warnings

Added Development Infrastructure

• Proper .gitignore: Excludes build artifacts, IDE files, and temporary files
• Clean repository state: Removed accidentally committed build artifacts

Testing

All deployment scenarios now work correctly:

# Local development
cargo run --bin api-gateway

# Docker container
docker build -f services/api/Dockerfile -t api-gateway .
docker run -p 3000:3000 api-gateway

# Full stack with Docker Compose
docker compose up --build

The API service is now properly accessible on port 3000 in all environments, with health checks confirming service availability.

Impact

• ✅ Unblocks containerized deployment - Docker builds and runs successfully
• ✅ Enables production deployment - Secure, optimized container images
• ✅ Improves developer experience - Clean builds, proper dependency management
• ✅ Maintains backward compatibility - No changes to existing API functionality

The "firewall" is now unblocked - the issue was infrastructure, not network configuration.

Original prompt

Firewall should not be blocked now. proceed

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