create
Creates a Client backed by an in-memory SQLCipher database.
Bypasses all on-disk database management — no .db3 file is created and no directory is touched. The returned client has Client.dbPath equal to IN_MEMORY_DB_PATH (":memory:") and Client.isInMemory returns true.
On in-memory clients, Client.deleteLocalDatabase, Client.dropLocalDatabaseConnection and Client.reconnectLocalDatabase are no-ops — state lives only in the FFI pool and is discarded when the client is garbage collected.
Intended for tests and other ephemeral flows where a real client is needed but persistence is not. ClientOptions.dbDirectory and ClientOptions.dbEncryptionKey are ignored — libxmtp manages the in-memory store itself.