chore: migrate from Drone CI to GitHub Actions (#147)

* chore: migrate from Drone CI to GitHub Actions

Replace .drone.star with a GitHub Actions workflow that builds
multi-arch Docker images (linux/amd64 + linux/arm64/v8) using
docker/build-push-action with buildx. All actions are pinned to
their release SHAs.

Consolidate the per-arch Dockerfiles (Dockerfile.amd64 /
Dockerfile.arm64v8) into a single Dockerfile.multiarch per
version, using BuildKit TARGETARCH/TARGETVARIANT to select the
correct base image. Chrome installation is guarded behind an
x86_64 check since no arm64 .deb is available.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

* fix: use multi-stage FROM to select base image per arch

TARGETVARIANT is not set by buildx for linux/arm64/v8 on GitHub-hosted
runners, so \${TARGETARCH}\${TARGETVARIANT} expanded to 'arm64' instead
of 'arm64v8', causing the build to fail with 'image not found'.

Replace the single parametric FROM with two named base stages and select
between them using TARGETARCH (which is reliably set to 'amd64' or
'arm64').

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

* chore: drop Node.js v14, v16, v18

Remove version directories and workflow matrix entries for EOL Node.js
versions 14, 16, and 18.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

* chore: use DOCKERHUB_USERNAME var and DOCKERHUB_TOKEN secret

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

* chore: drop latest version

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>

---------

Signed-off-by: Thomas Müller <1005065+DeepDiver1975@users.noreply.github.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: DeepDiver1975

.github/workflows/docker.yml

@@ -0,0 +1,53 @@
+name: Docker
+
+on:
+  push:
+    branches:
+      - master
+    tags:
+      - "**"
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        version:
+          - "24"
+          - "22"
+          - "20"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@06116385d9baf250c9f4dcb4858b16962ea869c3 # v4.1.0
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@d7f5e7f509e45cec5c76c4d5afdd7de93d0b3df5 # v4.1.0
+
+      - name: Login to Docker Hub
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@650006c6eb7dba73a995cc03b0b2d7f5ca915bee # v4.2.0
+        with:
+          username: ${{ vars.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Compute build context and tag
+        id: meta
+        run: |
+          echo "context=v${{ matrix.version }}" >> "$GITHUB_OUTPUT"
+          echo "tag=owncloudci/nodejs:${{ matrix.version }}" >> "$GITHUB_OUTPUT"
+
+      - name: Build and push
+        uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v7.2.0
+        with:
+          context: ${{ steps.meta.outputs.context }}
+          file: ${{ steps.meta.outputs.context }}/Dockerfile.multiarch
+          platforms: linux/amd64,linux/arm64/v8
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tag }}