* crypto.spec: make `keyResponder` a local var
it is never used between functions, so making it external was confusing
* Persist encryption state to the rust room list.
* `MatrixClient.shouldEncryptEventForRoom`: fix for rust crypto
Previously, we were not bothering to ask the Rust Crypto stack if it thought we
should be encrypting for a given room. This adds a new method to `CryptoApi`,
wires it up for legacy and Rust crypto, and calls it.
* Tests for persistent room list
* Store cross signing keys in secret storage
* Update `bootstrapSecretStorage` doc
* Throw error when `createSecretStorageKey` is not set
* Move mocking functions
* Store cross signing keys and user signing keys
* Fix `awaitCrossSigningKeyUpload` documentation
* Remove useless comment
* Fix formatting after merge conflict
* Move existing crypto integ tests into a subdirectory
* Factor out some common bits from `crypto.spec.ts`
* Integration test for device verification
* Ignore generated file in prettier