c657a123df
Add Docker Buildx support to build images for both linux/amd64 and linux/arm64 architectures using a single workflow. This enables deployment to ARM-based systems (e.g., Raspberry Pi, Apple Silicon) without separate builds. Changes: - Add Docker Buildx setup step to both backend and frontend jobs - Replace single-arch 'docker build' with multi-arch 'docker buildx build' - Configure '--platform linux/amd64,linux/arm64' for both architectures - Consolidate tag and push operations into single buildx command - Update evidence capture to include platform information - Update release summary to indicate multi-arch images Images will now be published as manifest lists containing both AMD64 and ARM64 variants under the same tags. Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode) Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>