Feat(medusa, user, core-flows): User creation with invites (#6413)

**What**
- add accept invite endpoint 

**Invite accept flow**
- authenticate using the auth endpoint to create and auth-user
- invoke accept endpoint with token and info to create user

packages/core-flows/src/invite/steps/validate-token.ts

@@ -0,0 +1,19 @@
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+import { InviteDTO } from "@medusajs/types"
+import { IUserModuleService } from "@medusajs/types"
+import { StepResponse } from "@medusajs/workflows-sdk"
+import { createStep } from "@medusajs/workflows-sdk"
+
+export const validateTokenStepId = "validate-invite-token-step"
+export const validateTokenStep = createStep(
+  validateTokenStepId,
+  async (input: string, { container }) => {
+    const userModuleService: IUserModuleService = container.resolve(
+      ModuleRegistrationName.USER
+    )
+
+    const invite = await userModuleService.validateInviteToken(input)
+
+    return new StepResponse(invite)
+  }
+)

packages/core-flows/src/invite/workflows/accept-invite.ts

@@ -0,0 +1,52 @@
+import { UserDTO } from "@medusajs/types"
+import {
+  WorkflowData,
+  createWorkflow,
+  transform,
+} from "@medusajs/workflows-sdk"
+import { createUsersStep } from "../../user"
+import { validateTokenStep } from "../steps/validate-token"
+import { setAuthAppMetadataStep } from "../../auth"
+import { InviteWorkflow } from "@medusajs/types"
+import { deleteInvitesStep } from "../steps"
+
+export const acceptInviteWorkflowId = "accept-invite-workflow"
+export const acceptInviteWorkflow = createWorkflow(
+  acceptInviteWorkflowId,
+  (
+    input: WorkflowData<InviteWorkflow.AcceptInviteWorkflowInputDTO>
+  ): WorkflowData<UserDTO[]> => {
+    // validate token
+    const invite = validateTokenStep(input.invite_token)
+
+    const createUserInput = transform(
+      { input, invite },
+      ({ input, invite }) => {
+        return [
+          {
+            ...input.user,
+            email: invite.email,
+          },
+        ]
+      }
+    )
+
+    const users = createUsersStep(createUserInput)
+
+    const authUserInput = transform({ input, users }, ({ input, users }) => {
+      const createdUser = users[0]
+
+      return {
+        authUserId: input.auth_user_id,
+        key: "user_id",
+        value: createdUser.id,
+      }
+    })
+
+    setAuthAppMetadataStep(authUserInput)
+
+    deleteInvitesStep([invite.id])
+
+    return users
+  }
+)

packages/core-flows/src/invite/workflows/index.ts

@@ -1,2 +1,3 @@
 export * from "./create-invites"
 export * from "./delete-invites"
+export * from "./accept-invite"