fix: Multi arch docker build

[hilariocoelho]

Docker build was hardcoded for amd64 only

[Copilot]

Pull request overview

This PR fixes the Docker build configuration to properly support multi-architecture builds instead of being hardcoded for amd64 only.

Changes:

• Removed hardcoded default value amd64 from TARGETARCH build argument
• Added TARGETOS build argument to support different operating systems
• Updated binary path in COPY instruction to use both TARGETOS and TARGETARCH variables

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[weinong]

can you add default os and arch?

[hilariocoelho]

What do you mean exactly with "default os and arch"? Those built arguments are already filled on docker buildx by specifying --platform argument (ie: docker build . --platform linux/amd64 --platform linux/arm64).

When setting ARG TARGETARCH=amd64, only amd64 binary is being included on both containers (linux/amd64 and linux/arm64).

On the github action it is already prepared for linux/amd64 and linux/arm64