Two adjustments to make CI pass:
- In gateway/platforms/matrix.py: `DeviceID` is `NewType("DeviceID", str)`,
so passing `client.device_id` directly (already a str) works identically
at runtime. The explicit import was cosmetic and tripped CI environments
where `mautrix.types` doesn't re-export DeviceID at the expected path
("cannot import name 'DeviceID' from 'mautrix.types' (unknown location)").
- In tests/gateway/test_matrix.py: add `put_device_id` to the hand-written
`PgCryptoStore` fake so the three encryption-path tests
(test_connect_with_access_token_and_encryption,
test_connect_uses_configured_device_id_over_whoami,
test_connect_registers_encrypted_event_handler_when_encryption_on) can
exercise the new crypto-store binding without AttributeError.
2182de55bb