feat: event aggregator (#6218)

What:
- Event Aggregator Util
- Preparation for normalizing event in a new format (backward compatible with the current format)
- GQL Schema to joiner config and some Entities configured
- Link modules emmiting events

packages/utils/src/modules-sdk/decorators/inject-into-context.ts

@@ -0,0 +1,30 @@
+export function InjectIntoContext(
+  properties: Record<string, unknown | Function>
+): MethodDecorator {
+  return function (
+    target: any,
+    propertyKey: string | symbol,
+    descriptor: any
+  ): void {
+    if (!target.MedusaContextIndex_) {
+      throw new Error(
+        `To apply @InjectIntoContext you have to flag a parameter using @MedusaContext`
+      )
+    }
+
+    const argIndex = target.MedusaContextIndex_[propertyKey]
+    const original = descriptor.value
+    descriptor.value = async function (...args: any[]) {
+      for (const key of Object.keys(properties)) {
+        args[argIndex] = args[argIndex] ?? {}
+        args[argIndex][key] =
+          args[argIndex][key] ??
+          (typeof properties[key] === "function"
+            ? (properties[key] as Function).apply(this, args)
+            : properties[key])
+      }
+
+      return await original.apply(this, args)
+    }
+  }
+}