All Submissions:

• Have you followed the WooCommerce Contributing guideline?
• Does your code follow the WordPress' coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

Add in the inventory manage stock section

Closes #34387 .

How to test the changes in this Pull Request:

1. Toggle site wide stock management at wp-admin/admin.php?page=wc-settings&tab=products&section=inventory
2. Check on the add new product page experience wp-admin/admin.php?page=wc-admin&path=%2Fadd-product that the inventory manage stock is shown or hidden based on your above selection.
3. Make sure that toggling Track quantity for this product opens the quantity management
4. Add negative values to fields to check that form validation errors appear
5. Check that the placeholder value for EMAIL ME WHEN QUANTITY REACHES matches the "Low stock threshold" quantity in wp-admin/admin.php?page=wc-settings&tab=products&section=inventory
6. Make sure settings persist upon save

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?
• Have you created a changelog file for each project being changed, ie pnpm --filter=<project> run changelog add?

FOR PR REVIEWER ONLY:

• I have reviewed that everything is sanitized/escaped appropriately for any SQL or XSS injection possibilities. I made sure Linting is not ignored or disabled.