Add database encryption for data at rest

[0x4E4448]

Is your feature request related to a problem? Please describe.
Data stored in the database is generally stored in plaintext. This is not a big issues for AIO or installs on the same server, but for installs using separate servers for NC and the database, particularly where the database server is not controlled by the NC operator, data can be easily viewed and compromised. In addition to NC server data, calendars, contacts, notes, etc could all be of concern.

Describe the solution you'd like
There should be an ability to encrypt data before or as it is written to the database. The key would likely be set in the NC config, but would help limit the exposure of data outside of the NC server itself.

Describe alternatives you've considered
Database-side encryption is a potential solution but would likely require different implementations for different servers. Implementing the encryption in NC itself would be database independent.

Additional context
My use case is having primary storage in object storage with server side encryption and a database I host, but a NC front-end my client hosts. I want to minimize the amount of data I control that can be read by myself or an attacker.

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Is your feature request related to a problem? Please describe.
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Describe the solution you'd like
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Describe alternatives you've considered
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Additional context
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[joshtrichards]

Duplicate of #13103