feat: add telemetry build provenance

Stamp official Docker builds with a low-cardinality provenance marker and report build_provenance/image_modified in anonymous telemetry. Local and fork builds default to custom, while official GitHub/GitLab release paths mark images as official.

scripts/docker-build-images.sh

@@ -6,12 +6,18 @@ IMAGE_NAMESPACE="${IMAGE_NAMESPACE:-3252a8}"
 IMAGE_TAG="${IMAGE_TAG:-local}"
 IMAGE_PREFIX="${IMAGE_PREFIX:-remnawave-minishop}"
 DOCKERFILE="${DOCKERFILE:-deploy/docker/Dockerfile}"
+REMNAWAVE_MINISHOP_BUILD_PROVENANCE="${REMNAWAVE_MINISHOP_BUILD_PROVENANCE:-custom}"
 
 build_image() {
   local target="$1"
   local image="$IMAGE_REGISTRY/$IMAGE_NAMESPACE/$IMAGE_PREFIX-$target:$IMAGE_TAG"
   echo "Building $image"
-  docker build -f "$DOCKERFILE" --target "$target" -t "$image" .
+  docker build \
+    -f "$DOCKERFILE" \
+    --target "$target" \
+    --build-arg "REMNAWAVE_MINISHOP_BUILD_PROVENANCE=$REMNAWAVE_MINISHOP_BUILD_PROVENANCE" \
+    -t "$image" \
+    .
 }
 
 build_image backend