Revert currentKeyboardLanguage change in emoji selector

[anperez]

ℹ️ This was originally opened as #1252, but closed accidentally while sync'ing branches.

Reverts a change to InputSources.swift introduced in 4fabc33 that made emoji search depend on the current keyboard layout (e.g., Spanish), rather than the system language (e.g., English).

This restores the previous behavior by using currentAppInputSource().uniqueElements instead of currentKeyboardLanguage(), ensuring emoji search results align with the system language preferences.

This should fix #1200

[anperez]

Hey @Redn4s, thanks a lot for the approval! Do you think we could get @overtake to merge this revert change at some point? It would fix a very annoying behavior in the client that we've been suffering for a while now (see #1200). Thanks!

[DuckyBlender]

bump, this is super annoying

[saarikivit]

Bump, I want this too! Super annoying.