ci: add teamcity build and deployment entry points

scripts/teamcity/rollback.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+: "${REGISTRY:?REGISTRY is required}"
+: "${APP_BASE_URL:?APP_BASE_URL is required}"
+
+if [[ ! -s .previous-image-tag ]]; then
+  echo "No previous image tag is available for rollback" >&2
+  exit 1
+fi
+
+IMAGE_TAG="$(cat .previous-image-tag)"
+export IMAGE_TAG REGISTRY
+
+docker compose pull edge api worker
+docker compose up -d --remove-orphans --wait --wait-timeout 120
+scripts/teamcity/smoke.sh
+printf '%s\n' "$IMAGE_TAG" > .deployed-image-tag