Report client status

[tobiasKaminsky]

See nextcloud/files-clients#45

[allexzander]

My ideas so far:

• Send sync status failure along with current log file in compressed form, mark current log file dirty in the local database, so it gets transferred to the server when complete (closed and zipped by logger)
• Every sent error can be recorded to the local database along with the file path and time stamp + error type, to avoid sending the same error and spamming the server
• Alternatively, each error is sent to the server allowing sending duplicates, but letting server accumulate such duplicates and display accordingly
• When sending sync errors, include required details explaining the reason for failure: server error with code and message, local problem with write permissions or disk space limit, other network errors related to bad connection or packet loss (not sure how possible this is now as we do not have network diagnostics feature)
• Differentiate errors based on specific scenarios: VFS hydration, E2E folder encryption or decryption, normal file syncing (uploads or downloads)
• Send errors for other features (sharing, local file editing, file lock and unlock feature)
• E2EE errors must be sent in such a way that encrypted files and folder names are not decrypted in such error reports (mangled names are kept)

[tobiasKaminsky]

• send data once a day
• check for capability on server
• do not send any data if there is nothing to report
• data format: error_code: count, earliest occurence, e.g: VIRUS_DETECTED: 1, 1698931253