As part of the Fedify 2.0 release preparation, we need to completely remove the deprecated @fedify/fedify/x/* modules from the next branch. These modules were already extracted into separate packages in #375/#388 and will be marked as deprecated in the upcoming 1.9.0 release.

The affected modules under @fedify/fedify/x/* have been replaced with their standalone package counterparts (e.g., @fedify/sveltekit, @fedify/hono, etc.), and users have been given sufficient time to migrate. Now it's time to clean up the codebase by removing these deprecated exports entirely from the main package.