Improved Local backend detection (#4006)

Co-authored-by: 6543 <6543@obermui.de>

docker/Dockerfile.agent.alpine.multiarch

@@ -10,6 +10,8 @@ RUN --mount=type=cache,target=/root/.cache/go-build \
 FROM docker.io/alpine:3.20
 RUN apk add -U --no-cache ca-certificates
 ENV GODEBUG=netdns=go
+# Internal setting do NOT change! Signals that woodpecker is running inside a container
+ENV WOODPECKER_IN_CONTAINER=true
 EXPOSE 3000
 
 COPY --from=build /src/dist/woodpecker-agent /bin/

docker/Dockerfile.agent.multiarch

@@ -10,6 +10,8 @@ RUN mkdir -p /etc/woodpecker
 
 FROM scratch
 ENV GODEBUG=netdns=go
+# Internal setting do NOT change! Signals that woodpecker is running inside a container
+ENV WOODPECKER_IN_CONTAINER=true
 EXPOSE 3000
 
 # copy certs from build image