* Add labs option to exclude unverified devices
Add a labs option which will, when set, switch into the "invisible crypto"
mode of refusing to send keys to, or decrypt messages from, devices that have
not been signed by their owner.
* DecryptionFailureBody: better error messages
Improve the error messages shown for messages from insecure devices.
* playwright: factor out `createSecondBotDevice` utility
* Playwright test for messages from insecure devices
* fixup! DecryptionFailureBody: better error messages
Use compound colour tokens, and add a background colour.
* fixup! DecryptionFailureBody: better error messages
Use compound spacing tokens
* Remove refs to deprecated method
`MatrixEvent.isEncryptedDisabledForUnverifiedDevices` is now deprecated
* Report new posthog code for withheld message keys
* Use different messages for UTDs sent before login
* Playwright test for historical events
* Add some tests
* initial work on pre-join UTDs
* add playwright tests and remove old pre-join UTD logic
* run i18n script
* fix type error
* use different error code in PostHog for pre-join UTD
* don't remove old pre-join UTD logic yet
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Co-authored-by: Richard van der Hoff <richard@matrix.org>
* Use different messages for UTDs sent before login
* Playwright test for historical events
* Add some tests
* Don't show "verify" message if backup is working
* Apply suggestions from code review