Element-R: Cross-user verification

[florianduros]

https://docs.google.com/document/d/18LuSmlaoeZpsOsiPKIdAxKYsbr9V1etMAYm2vxMId7A/edit#heading=h.ru8oinr04fz7

Tasks

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1. ElementR: Add CryptoApi.findVerificationRequestDMInProgress matrix-org/matrix-js-sdk#3601
   T-Enhancement +1
2. ElementR: Provide userId parameter to findVerificationRequestDMInProgress matrix-org/matrix-react-sdk#11292
   T-Task +1
3. ElementR: Throw error if missing userId in CryptoApi.findVerificationRequestDMInProgress matrix-org/matrix-js-sdk#3641
   T-Task +1
4. ElementR: Add CryptoApi.requestVerificationDM matrix-org/matrix-js-sdk#3643
   T-Enhancement +1
5. ElementR: Update CryptoApi.userHasCrossSigningKeys matrix-org/matrix-js-sdk#3646
   T-Enhancement +1
6. ElementR: Track untracked users in CryptoApi.getUserDeviceInfo matrix-org/matrix-js-sdk#3649
   T-Defect +1
7. ElementR: Process all verification events, not just requests matrix-org/matrix-js-sdk#3650
   T-Defect +1
8. Deprecate MatrixClient.checkUserTrust matrix-org/matrix-js-sdk#3691
   T-Deprecation +1
9. ElementR: Cross user verification matrix-org/matrix-react-sdk#11364
   T-Enhancement +1
10. Enable cypress tests to run with rust-crypto
11. https://github.com/vector-im/crypto-internal/issues/148