Request: Provide a multiarch Docker image with arm64 support

The official Docker image currently supports only the amd64 architecture.
Many users today deploy Rocket.Chat on arm64-based environments such as:

• Raspberry Pi devices
• NAS systems (Synology, TrueNAS, etc.)
• Home servers
• Cloud or VPS providers offering ARM instances

Adding multi-architecture support (amd64 and arm64) would offer several benefits:

• 🧩 Wider compatibility: Rocket.Chat could run on a broader range of hardware without manual rebuilds.
• 🔄 Simplified maintenance: Users could update directly from Docker Hub without building custom images.
• 🔐 Consistent security: Ensures all platforms receive the same updates and patches simultaneously.
• ⚙️ Improved CI/CD workflows: Easier integration into modern multiarch pipelines and container environments.
• 🌱 Energy efficiency: Enables deployments on low-power, cost-effective ARM devices used by small teams and hobbyists.

Multiarch builds can be implemented easily using Docker Buildx or similar tools in the existing CI workflow.
This enhancement would make Rocket.Chat more accessible and reliable across all platforms.

Thank you for considering this improvement and for maintaining such a great open source project.

Locate the existing CI workflow that builds and publishes the official Docker image, then read how its current architecture is selected. Use Docker Buildx or the existing workflow tooling as the starting point; done means the published image supports both amd64 and arm64 without manual rebuilding.