Feat: Add support for /operations/schema_changes endpoint

[nikspyratos]

Change Summary

Basic implementation for the schema changes endpoint, where you'd check a collection schema update's status: https://typesense.org/docs/29.0/api/collections.html#get-schema-change-status

From a skim of the repo I hadn't found a similar usage of adding a subpath under the RESOURCE_PATH, so just made a best-guess effort.

Tested these changes in a Laravel repo I'm working with. Cropped to exclude any potential business info:

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