Per document review meeting, we've decided to move the check for whether a command should undergo auto encryption from the driver into libmongocrypt. This requires a change to mongocrypt_ctx_encrypt_init to take the full command instead of just the namespace.

In addition, now for MONGOCRYPT_CTX_MONGO_NEED_MARKINGS, instead of just returning the jsonSchema, we can return the full command to be sent to mongocryptd.