Fix Docker build failure: remove unsupported ARM platform variants

[Copilot]

Docker builds were failing with "no match for platform in manifest" because the workflow attempted to build for linux/arm/v7 and linux/arm/v8, which are not supported by node:24.10.0-bullseye-slim.

Changes

• Removed linux/arm/v7 (32-bit ARM, unsupported by Node.js 24.x images)
• Removed linux/arm/v8 (incorrect notation, duplicate of linux/arm64)
• Retained linux/amd64 and linux/arm64 which are supported by both base images

The workflow now builds only for platforms available in the Node.js Docker images:

matrix:
  include:
    - dockerfile: Dockerfile.alpine
      platform: linux/amd64
    - dockerfile: Dockerfile
      platform: linux/arm64

Original prompt

My Docker pipeline is failing with:

Dockerfile:1
--------------------
   1 | >>> FROM node:24.10.0-bullseye-slim AS builder
   2 |     RUN corepack enable
   3 |     
--------------------
ERROR: failed to build: failed to solve: node:24.10.0-bullseye-slim: failed to resolve source metadata for docker.io/library/node:24.10.0-bullseye-slim: no match for platform in manifest: not found
Reference
  builder-265fecaf-42da-4f08-a0a6-7059abdb2f9f/builder-265fecaf-42da-4f08-a0a6-7059abdb2f9f0/vjw511uvs5wqseeyrrfeakd5b
Check build summary support
Error: buildx failed with: ERROR: failed to build: failed to solve: node:24.10.0-bullseye-slim: failed to resolve source metadata for docker.io/library/node:24.10.0-bullseye-slim: no match for platform in manifest: not found

Please identify the root cause and address it.

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