Chore/rm main entity concept (#7709)

**What**
Update the `MedusaService` class, factory and types to remove the concept of main modules. The idea being that all method will be explicitly named and suffixes to represent the object you are trying to manipulate.
This pr also includes various fixes in different modules

Co-authored-by: Stevche Radevski <4820812+sradevski@users.noreply.github.com>
Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/modules/file/integration-tests/__tests__/module.spec.ts

@@ -1,7 +1,8 @@
 import { resolve } from "path"
 import { Modules } from "@medusajs/utils"
-import { SuiteOptions, moduleIntegrationTestRunner } from "medusa-test-utils"
+import { moduleIntegrationTestRunner } from "medusa-test-utils"
 import { Entity, PrimaryKey } from "@mikro-orm/core"
+import { IFileModuleService } from "@medusajs/types"
 
 jest.setTimeout(100000)
 
@@ -28,15 +29,14 @@ const moduleOptions = {
   ],
 }
 
-moduleIntegrationTestRunner({
+moduleIntegrationTestRunner<IFileModuleService>({
   moduleName: Modules.FILE,
   moduleOptions: moduleOptions,
   moduleModels: [DummyEntity],
-  // TODO: Fix the type of service, it complains for some reason if we pass IFileModuleService
-  testSuite: ({ service }: SuiteOptions<any>) => {
+  testSuite: ({ service }) => {
     describe("File Module Service", () => {
       it("creates and gets a file", async () => {
-        const res = await service.create({
+        const res = await service.createFiles({
           filename: "test.jpg",
           mimeType: "image/jpeg",
           content: Buffer.from("test"),
@@ -48,7 +48,7 @@ moduleIntegrationTestRunner({
         })
 
         // The fake provider returns the file content as the url
-        const downloadUrl = await service.retrieve("test.jpg")
+        const downloadUrl = await service.retrieveFile("test.jpg")
         expect(await new Response(downloadUrl.url).text()).toEqual("test")
       })
     })