fix: make Transaction private

For the time being, it is better to hide the `Transaction` type since actions
might need to stay fine-grained.

src/lib.rs

@@ -679,7 +679,7 @@ where
     }
 
     /// Apply COB operations to a `JobMut`.
-    pub fn transaction<G, F>(
+    fn transaction<G, F>(
         &mut self,
         message: &str,
         signer: &Device<G>,
@@ -701,7 +701,7 @@ where
 
 /// An update for the `Job` COB. This applies a change to the
 /// in-memory computed representation of the COB.
-pub struct Transaction<R: ReadRepository>(store::Transaction<Job, R>);
+struct Transaction<R: ReadRepository>(store::Transaction<Job, R>);
 
 impl<R> From<store::Transaction<Job, R>> for Transaction<R>
 where
@@ -755,17 +755,17 @@ where
     R: ReadRepository,
 {
     /// Add a request operation to the transaction.
-    pub fn request(&mut self, oid: Oid) -> Result<(), store::Error> {
+    fn request(&mut self, oid: Oid) -> Result<(), store::Error> {
         self.0.push(Action::Request { oid })
     }
 
     /// Add a new `Run` to a transaction.
-    pub fn run(&mut self, uuid: Uuid, log: Url) -> Result<(), store::Error> {
+    fn run(&mut self, uuid: Uuid, log: Url) -> Result<(), store::Error> {
         self.0.push(Action::Run { uuid, log })
     }
 
     /// Mark a run as finished.
-    pub fn finish(&mut self, uuid: Uuid, reason: Reason) -> Result<(), store::Error> {
+    fn finish(&mut self, uuid: Uuid, reason: Reason) -> Result<(), store::Error> {
         self.0.push(Action::Finished { uuid, reason })
     }
 }