ci: configure runner to use host mode with mips-builder label

docker/runner/entrypoint.sh

@@ -5,10 +5,13 @@ set -e
 if [ -n "$GITEA_INSTANCE_URL" ] && [ -n "$GITEA_RUNNER_TOKEN" ]; then
     if [ ! -f ".runner" ]; then
         echo "Registering runner..."
+        # Register with label 'mips-builder' valid for host execution
+        # plus 'ubuntu-latest' mapped to host for convenience if needed
         act_runner register \
           --instance "$GITEA_INSTANCE_URL" \
           --token "$GITEA_RUNNER_TOKEN" \
-          --name "custom-mips-runner-$(hostname)" \
+          --name "vibetorrent-mips-runner-$(hostname)" \
+          --labels "mips-builder:host,ubuntu-latest:host" \
           --no-interactive
     else
         echo "Runner already registered."