fix: some compile time errors

Only 174 errors left!

src/service/transaction_ids/data.rs

@@ -1,5 +1,5 @@
 pub trait Data {
-    pub fn add_txnid(
+    fn add_txnid(
         &self,
         user_id: &UserId,
         device_id: Option<&DeviceId>,
@@ -7,7 +7,7 @@ pub trait Data {
         data: &[u8],
     ) -> Result<()>;
 
-    pub fn existing_txnid(
+    fn existing_txnid(
         &self,
         user_id: &UserId,
         device_id: Option<&DeviceId>,

src/service/transaction_ids/mod.rs

@@ -1,5 +1,6 @@
 mod data;
 pub use data::Data;
+use ruma::{UserId, DeviceId, TransactionId};
 
 use crate::service::*;