feat(medusa,utils,core-flows): add reset password metdata (#14417)

## Summary

**What**

Adds metadata field for reset password route that allows passing data from caller that can be found in the subscriber. 

## Checklist

Please ensure the following before requesting a review:

- [x] I have added a **changeset** for this PR
    - Every non-breaking change should be marked as a **patch**
    - To add a changeset, run `yarn changeset` and follow the prompts
- [x] The changes are covered by relevant **tests**
- [x] I have verified the code works as intended locally
- [ ] I have linked the related issue(s) if applicable


---

> [!NOTE]
> Introduces optional request `metadata` for reset-password and propagates it through to event subscribers.
> 
> - Accepts `metadata` in `ResetPasswordRequest` validator and `reset-password` route; forwards it to `generateResetPasswordTokenWorkflow`
> - Workflow now accepts `metadata` and includes it in emitted `auth.password_reset` event data
> - Updates event docs to mention `metadata` field
> - Adds integration test verifying `metadata` is emitted in the password reset event
> 
> <sup>Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit 7f9855feabed284336e8872eebfb18fe3bd320db. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).</sup>

packages/medusa/src/api/auth/[actor_type]/[auth_provider]/reset-password/route.ts

@@ -11,7 +11,7 @@ export const POST = async (
   res: MedusaResponse
 ) => {
   const { auth_provider, actor_type } = req.params
-  const { identifier } = req.validatedBody
+  const { identifier, metadata } = req.validatedBody
 
   const { http } = req.scope.resolve(
     ContainerRegistrationKeys.CONFIG_MODULE
@@ -24,6 +24,7 @@ export const POST = async (
       provider: auth_provider,
       secret: http.jwtSecret!,
       jwtOptions: http.jwtOptions,
+      metadata,
     },
     throwOnError: false, // we don't want to throw on error to avoid leaking information about non-existing identities
   })

packages/medusa/src/api/auth/validators.ts

@@ -2,5 +2,6 @@ import { z } from "zod"
 
 export const ResetPasswordRequest = z.object({
   identifier: z.string(),
+  metadata: z.record(z.unknown()).optional().default({}),
 })
 export type ResetPasswordRequestType = z.infer<typeof ResetPasswordRequest>