[Meta] Error handling

[michaelstingl]

Idea: Error should be handled on the server-side and only displayed in the app. Sometimes it's necessary to persist the error for status messages or logging. If the server error message isn't clear, please get in touch with server team to improve here. Please also check if translation of error messages can also be done on the server. We need to check if clients are able to request the preferred language.

• Quota (Check Error message for Insufficient Storage error android#1767 for inspiration? Server issue: Insufficient Storage error handling core#31284)
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