Feat(core-flows, inventory-next, medusa, types): Add create location level endpoint (#6695)

* initialize create location levels

* add enough from pr to make code build and test

* fix integration tests

* pr feedback

* fix errors

* rm dto

* Update packages/core-flows/src/inventory/steps/validate-inventory-locations.ts

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

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

integration-tests/plugins/package.json

@@ -16,6 +16,7 @@
     "@medusajs/customer": "workspace:^",
     "@medusajs/event-bus-local": "workspace:*",
     "@medusajs/inventory": "workspace:^",
+    "@medusajs/inventory-next": "workspace:^",
     "@medusajs/medusa": "workspace:*",
     "@medusajs/modules-sdk": "workspace:^",
     "@medusajs/pricing": "workspace:^",