feat: добавить генерацию image variants

- добавлен shared config presets, custom transforms и allowlist hosts
- реализованы Backend endpoints для assets, presets и variants
- добавлена orchestration через PostgreSQL, RabbitMQ, S3 и worker
- обновлён Gateway read-through flow с L1 cache и корректным Vary: Accept
- добавлена миграция resize_mode для variants lookup
- обновлены dev scripts, env template, lockfile и документация

apps/worker/src/config.ts

@@ -1,19 +1,34 @@
 import { loadQueueTopologyFromEnv, type QueueTopology } from "@image-platform/queue"
+import { loadStorageConfigFromEnv, type StorageConfig } from "@image-platform/storage"
 
 export type WorkerConfig = {
+  imgproxyUpstream: URL
   prefetch: number
   queueTopology: QueueTopology
   rabbitmqUrl: string
+  storage: StorageConfig
 }
 
 export function loadWorkerConfig(env: NodeJS.ProcessEnv = process.env): WorkerConfig {
   return {
+    imgproxyUpstream: new URL(getRequiredEnv(env, "IMGPROXY_UPSTREAM")),
     prefetch: parsePositiveInteger(env.WORKER_PREFETCH, 2),
     queueTopology: loadQueueTopologyFromEnv(env),
-    rabbitmqUrl: env.RABBITMQ_URL ?? "amqp://image:image-password@localhost:5672/image_platform",
+    rabbitmqUrl: getRequiredEnv(env, "RABBITMQ_URL"),
+    storage: loadStorageConfigFromEnv(env),
   }
 }
 
+function getRequiredEnv(env: NodeJS.ProcessEnv, name: string) {
+  const value = env[name]
+
+  if (!value) {
+    throw new Error(`${name} is required`)
+  }
+
+  return value
+}
+
 function parsePositiveInteger(value: string | undefined, fallback: number) {
   if (!value) {
     return fallback