import $page from $app/stores in library

[benjaminpreiss]

Dear community,

Have been searching a lot, but I didn't find an answer to my question on how to enable importing page from $app/stores in a library build.

Here is an example for usage in a library: https://github.com/frontline-hq/sveltekit-i18n/blob/09b9c7b62e17661a7d5c8dbf1585132ff7b29f0a/src/lib/index.ts#L2

When I want to use that library in another sveltekit project, I get the error:

Error [ERR_MODULE_NOT_FOUND]: Cannot find package '$app' imported from /Users/**********/Documents/work/*********/node_modules/@frontline-hq/sveltekit-i18n/index.js
    at new NodeError (node:internal/errors:393:5)
    at packageResolve (node:internal/modules/esm/resolve:860:9)
    at moduleResolve (node:internal/modules/esm/resolve:909:20)
    at defaultResolve (node:internal/modules/esm/resolve:1124:11)
    at nextResolve (node:internal/modules/esm/loader:163:28)
    at ESMLoader.resolve (node:internal/modules/esm/loader:841:30)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:424:18)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:76:40)
    at link (node:internal/modules/esm/module_job:75:36)

Related issues:
#1485
#6449
#3010

Does anyone know now, how to correctly configure vite / the sveltekit build to allow using $app/* imports?

Help greatly appreciated!