ci: run on any runner, amd64 or arm64

The builder image is now multi-arch (linux/amd64 + linux/arm64, pushed
as srfplay-builder:latest after building all three plugin zips in each
variant), so jobs no longer need an amd64 host. runs-on moves from
linux/amd64 to ubuntu-latest, which draco-x86, freebox and oracle-a1
all carry, so a job no longer waits behind long jobs on draco while
the ARM runners sit idle.

.gitea/runner/cloud-init.yaml sets up such a runner on an Oracle Cloud
Always Free Ampere VM (Ubuntu 24.04): Docker, act_runner registered
instance-wide with the instance's label set, and a weekly image prune.
The registration token and the optional console password hash are
placeholders here and must be filled in locally before use.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.gitea/runner/cloud-init.yaml

@@ -0,0 +1,58 @@
+#cloud-config
+# Gitea Actions runner on an Oracle Cloud Always Free Ampere (ARM) VM, shared by
+# every repo on the instance.
+#
+# Paste this into "Advanced options -> Management -> Initialization script" when
+# creating the instance (image: Canonical Ubuntu 24.04, shape: VM.Standard.A1.Flex).
+# Before pasting, replace REGISTRATION_TOKEN below with an instance-wide token:
+#   Site Administration -> Actions -> Runners -> Create new runner
+# (a token from repo Settings would limit the runner to that one repo).
+#
+# The runner only makes outbound connections (to Gitea and container registries),
+# so the VM needs no inbound ports beyond SSH.
+#
+# Labels follow the instance convention (same set as the freebox ARM runner).
+# ubuntu-latest / ubuntu-22.04 are shared with the amd64 runner, so a job asking
+# for them may land on either architecture; ask for linux/arm64 or linux/amd64
+# when a job needs a specific one. SRF Play jobs run in the multi-arch
+# srfplay-builder image, so they work on both.
+
+# Optional: a password for the "ubuntu" user, so you can log in through the Oracle
+# serial console ("Launch Cloud Shell connection") without an SSH key. Generate the
+# hash locally with:  openssl passwd -6
+# then uncomment and paste it in. SSH still only accepts keys.
+#chpasswd:
+#  expire: false
+#  users:
+#    - name: ubuntu
+#      password: "$6$...paste the hash here..."
+
+package_update: true
+packages:
+  - docker.io
+  - docker-compose-v2
+
+write_files:
+  - path: /opt/act_runner/docker-compose.yml
+    permissions: "0600"
+    content: |
+      services:
+        runner:
+          image: gitea/act_runner:latest
+          restart: unless-stopped
+          environment:
+            GITEA_INSTANCE_URL: https://gitea.tourolle.paris
+            GITEA_RUNNER_REGISTRATION_TOKEN: REGISTRATION_TOKEN
+            GITEA_RUNNER_NAME: oracle-a1
+            # Comma-separated with no spaces: label:docker://<default job image>
+            GITEA_RUNNER_LABELS: "ubuntu-latest:docker://gitea/runner-images:ubuntu-latest,ubuntu-22.04:docker://gitea/runner-images:ubuntu-22.04,linux-arm64:docker://gitea/runner-images:ubuntu-latest,self-hosted:docker://gitea/runner-images:ubuntu-latest,linux/arm64:docker://gitea/runner-images:ubuntu-latest"
+          volumes:
+            # Registration is stored here, so the token is only used once.
+            - ./data:/data
+            - /var/run/docker.sock:/var/run/docker.sock
+
+runcmd:
+  - systemctl enable --now docker
+  - cd /opt/act_runner && docker compose up -d
+  # Weekly clean-up so pulled images and build caches do not fill the boot volume.
+  - echo '0 4 * * 0 root docker system prune -af --filter "until=168h" >/dev/null 2>&1' > /etc/cron.d/docker-prune

.gitea/workflows/build.yaml

@@ -15,7 +15,7 @@ on:
 
 jobs:
   build:
-    runs-on: linux/amd64
+    runs-on: ubuntu-latest
     container:
       image: gitea.tourolle.paris/dtourolle/srfplay-builder:latest
 

.gitea/workflows/latest.yaml

@@ -11,7 +11,7 @@ on:
 
 jobs:
   nightly-build:
-    runs-on: linux/amd64
+    runs-on: ubuntu-latest
     container:
       image: gitea.tourolle.paris/dtourolle/srfplay-builder:latest
 

.gitea/workflows/release.yaml

@@ -13,7 +13,7 @@ on:
 
 jobs:
   build-and-release:
-    runs-on: linux/amd64
+    runs-on: ubuntu-latest
     container:
       image: gitea.tourolle.paris/dtourolle/srfplay-builder:latest
 

.gitea/workflows/test.yaml

@@ -17,7 +17,7 @@ on:
 
 jobs:
   test:
-    runs-on: linux/amd64
+    runs-on: ubuntu-latest
     container:
       image: gitea.tourolle.paris/dtourolle/srfplay-builder:latest
 

Dockerfile.builder

@@ -1,7 +1,10 @@
 # SRFPlay Builder Image
 # Pre-built image with .NET SDK and JPRM for building Jellyfin plugins
-# Build: docker build -f Dockerfile.builder -t gitea.tourolle.paris/dtourolle/srfplay-builder:latest .
-# Push:  docker push gitea.tourolle.paris/dtourolle/srfplay-builder:latest
+# Multi-arch (amd64 + arm64) so runners on ARM hosts such as Oracle Cloud's free
+# Ampere VMs can use it too; the plugin DLLs it produces are identical either way.
+# Build + push (needs a docker-container buildx builder and arm64 binfmt/QEMU):
+#   docker buildx build -f Dockerfile.builder --platform linux/amd64,linux/arm64 \
+#       -t gitea.tourolle.paris/dtourolle/srfplay-builder:latest --push .
 
 FROM mcr.microsoft.com/dotnet/sdk:10.0