fix(kestra-init): use alpine+curl instead of kestra image to avoid 413

kestra/kestra:latest is ~500MB; the registry rejects the push.
The init container only needs to POST flow YAMLs to the Kestra REST API
(/api/v1/flows/import), which curl handles fine from a tiny alpine base.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

integrator/Dockerfile.init

@@ -1,3 +1,6 @@
-FROM kestra/kestra:latest
+FROM alpine:3.19
+RUN apk add --no-cache curl
 COPY flows/ /flows/
-CMD ["flow", "namespace", "update", "schoolcompare.data", "/flows", "--no-delete"]
+COPY docker/kestra-init.sh /kestra-init.sh
+RUN chmod +x /kestra-init.sh
+CMD ["/kestra-init.sh"]

integrator/docker/kestra-init.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+set -e
+
+KESTRA_URL="${KESTRA_URL:-http://kestra:8080}"
+
+echo "Importing flows into Kestra at ${KESTRA_URL}..."
+
+for f in /flows/*.yml; do
+  echo "  -> $(basename "$f")"
+  curl -sf -X POST "${KESTRA_URL}/api/v1/flows/import" \
+    -H "Content-Type: multipart/form-data" \
+    -F "fileUpload=@${f}" \
+    || { echo "Failed to import $(basename "$f")"; exit 1; }
+  echo ""
+done
+
+echo "All flows imported."