ARM64 Compatibility

[igarridot]

Enable ARM64 Build Support

Summary

This PR adds multi-architecture Docker image support, enabling builds for both linux/amd64 and linux/arm64 platforms.

Changes

GitHub Actions Workflow (.github/workflows/docker-image.yml)

• Added QEMU setup for cross-platform emulation
• Added Docker Buildx for multi-platform builds
• Enabled linux/amd64,linux/arm64 platform targets
• Added GitHub Actions cache for faster builds

Dockerfile

• Implemented dynamic architecture detection using TARGETARCH build argument
• Added conditional Rust target selection (x86_64 vs aarch64)
• Modified build commands to use architecture-specific targets
• Unified binary output path for consistent runtime stage

Dependencies (pentaract/Cargo.toml)

• Replaced OpenSSL with rustls-tls in reqwest to avoid cross-compilation issues with native OpenSSL libraries

Why

ARM64 support enables running Pentaract on Apple Silicon Macs, AWS Graviton instances, and other ARM-based infrastructure, improving deployment flexibility and reducing costs on ARM
platforms.