[v0.18.x] User Locale and Appearance settings are not being recovered from database

[lincolnthalles]

Describe the bug

Locale and appearance settings are being stored in the browser and also in the database just fine, but if you clear the browser storage and re-login, you will need to set those settings again.

I guess the appearance and locale set at login screen are just being respected, but this makes the database storage of these settings useless.

The fix is probably not so straightforward. Maybe the user data should always be recovered and whatever is set at login screen should only be saved if there's nothing in the user profile or if the user actually changed those values and the defaults are not being used.

This doesn't affect v0.17.1 and previous versions.

Steps to reproduce

1. Log-in to memos
2. Set a language and appearance
3. Clear browser cache, clear just website cookies and data or log-in on another browser
4. You will have to set the language and appearance again

The version of Memos you're using

v0.18.0, v0.18.1

Screenshots or additional context

No response