Add setting to only share message keys to verified devices (of verified/TOFU users)

[Nep Nep]

The Problem

Currently, the closest option is to enable the setting that causes nheko to only share keys with manually verified users, which can be prohibitively time consuming.

The Solution

By having a setting to share keys with users' verified devices even if the users themselves aren't manually verified, as long as their original master key is used, you still gain a security benefit compared to always sharing keys (as long as users don't verify unknown devices), but without nearly as much hassle.

Alternatives

No response

Additional context

The discussion starting at https://matrix.to/#/%23nheko%3Anheko.im/%24ZEEY_Y4v1ic7syYLCTfb7Svda1tZtSSbQiY86Cc1hbY?via=neko.dev&via=matrix.org&via=envs.net (in nheko's official development room).

Happens in the latest version

• Yes, this feature is still missing.