feat: add history tail for live monitoring view (#3389)

Useful for watching what agents are doing, or viewing live info from
other machines. Regardless I am liking it for debugging

## Checks
- [ ] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [ ] I have checked that there are no existing pull requests for the
same thing

1 files changed, 50 insertions, 0 deletions

diff --git a/crates/atuin-daemon/tests/lifecycle.rs b/crates/atuin-daemon/tests/lifecycle.rs
index 3b6952de..4a91e5cb 100644
--- a/crates/atuin-daemon/tests/lifecycle.rs
+++ b/crates/atuin-daemon/tests/lifecycle.rs
@@ -146,6 +146,56 @@ mod unix {
     }
 
     #[tokio::test]
+    async fn test_tail_history_streams_started_and_ended_events() {
+        use atuin_client::history::History;
+        use atuin_daemon::history::HistoryEventKind;
+
+        let (mut client, _handle, _tmp) = start_test_daemon().await;
+        let mut stream = client.tail_history().await.unwrap();
+
+        let history = History::daemon()
+            .timestamp(time::OffsetDateTime::now_utc())
+            .command("git status".to_string())
+            .cwd("/tmp/repo".to_string())
+            .session("tail-session".to_string())
+            .hostname("test-host:ellie".to_string())
+            .author("claude".to_string())
+            .intent("inspect repository state".to_string())
+            .build()
+            .into();
+
+        let start_reply = client.start_history(history).await.unwrap();
+
+        let started = stream.message().await.unwrap().unwrap();
+        assert_eq!(
+            HistoryEventKind::try_from(started.kind).unwrap(),
+            HistoryEventKind::Started
+        );
+        let started_history = started.history.unwrap();
+        assert_eq!(started_history.id, start_reply.id);
+        assert_eq!(started_history.command, "git status");
+        assert_eq!(started_history.cwd, "/tmp/repo");
+        assert_eq!(started_history.hostname, "test-host:ellie");
+        assert_eq!(started_history.author, "claude");
+        assert_eq!(started_history.intent, "inspect repository state");
+
+        client
+            .end_history(start_reply.id.clone(), 1_000_000, 0)
+            .await
+            .unwrap();
+
+        let ended = stream.message().await.unwrap().unwrap();
+        assert_eq!(
+            HistoryEventKind::try_from(ended.kind).unwrap(),
+            HistoryEventKind::Ended
+        );
+        let ended_history = ended.history.unwrap();
+        assert_eq!(ended_history.id, start_reply.id);
+        assert_eq!(ended_history.exit, 0);
+        assert_eq!(ended_history.duration, 1_000_000);
+    }
+
+    #[tokio::test]
     async fn test_end_unknown_history_fails() {
         let (mut client, _handle, _tmp) = start_test_daemon().await;