fix(server): remove auth from Obtainium android-links endpoint and change android to apk, now apk-links

[NicholasFlamy]

Description

I removed the @Authenticated() tag because the version endpoint doesn't have auth and this endpoint is literally just the GitHub releases apk links but with the server version. Also, I think we decided apk instead of android, but I didn't update that everywhere (oops).
Renames and removes auth from #18700

How Has This Been Tested?

• make dev

API Changes

The /api/server/android-links endpoint is now /api/server/apk-links and it no longer requires auth.

Checklist:

• I have performed a self-review of my own code
• I have no unrelated changes in the PR.
• I have followed naming conventions/patterns in the surrounding code
• All code in src/services/ uses repositories implementations for database calls, filesystem operations, etc.
• All code in src/repositories/ is pretty basic/simple and does not have any immich specific logic (that belongs in src/services/)

[danieldietzler]

I don't think /server/version and /server/version-history should be public actually. There's no reason they cannot require auth, right? @jrasm91

[jrasm91]

Idk. This is a bigger discussion. Let's decide on discord, make a decision, and then make the appropriate changes.

Some things can't require auth, like whether oauth is enabled or not, since we need to know whether to show the button on the login page or not.

[NicholasFlamy]

Let's decide on discord, make a decision, and then make the appropriate changes.

Alright, please let me know when y'all decide. If y'all decide to add auth to the version endpoint, I'll update this PR to keep auth.

[NicholasFlamy]

Closing and replacing with #18790 because I wanted the branch name to be more accurate.