feat: добавить Image Gateway с кешем Souin

- добавлена сборка Caddy с Souin, Otter и NutsDB

- добавлена конфигурация dev, prod и test Docker Compose

- настроено кеширование через Otter L1 и NutsDB L2

- добавлены e2e-тесты Bun для кеша, restart и purge

- добавлена документация по запуску, API кеша и тестам

scripts/test-e2e.sh

@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+project_name="${COMPOSE_PROJECT_NAME:-image-gateway-test-${CI_JOB_ID:-${GITHUB_RUN_ID:-local}}}"
+compose=(docker compose -p "${project_name}" -f docker-compose.test.yml)
+
+cleanup() {
+  status=$?
+
+  if [ "${status}" -ne 0 ]; then
+    "${compose[@]}" logs --no-color || true
+  fi
+
+  "${compose[@]}" down -v --remove-orphans >/dev/null 2>&1 || true
+  exit "${status}"
+}
+
+trap cleanup EXIT
+
+"${compose[@]}" down -v --remove-orphans >/dev/null 2>&1 || true
+"${compose[@]}" up -d --build caddy imgproxy fixture
+
+"${compose[@]}" run --rm tester bun test tests/e2e/cache-prime.test.js
+
+"${compose[@]}" restart caddy
+"${compose[@]}" run --rm tester bun test tests/e2e/cache-persistence.test.js
+
+"${compose[@]}" run --rm tester bun test tests/e2e/cache-purge.test.js
+
+logs=$("${compose[@]}" logs --no-color caddy)
+
+case "${logs}" in
+  *"default storage that is not optimized"*)
+    printf '%s\n' "Caddy logs contain Souin default storage warning"
+    exit 1
+    ;;
+esac
+
+case "${logs}" in
+  *"NUTS-INSERTION-ERROR"*)
+    printf '%s\n' "Caddy logs contain NUTS-INSERTION-ERROR"
+    exit 1
+    ;;
+esac
+
+printf '%s\n' "E2E cache tests passed"