application: channels bounded context

CQRS use cases (create/update/delete/get/list/list_by_owner),
ownership checks, auto-snapshot on config change.
Channel setters added to domain model.

crates/application/src/channels/tests/get.rs

@@ -0,0 +1,66 @@
+use std::sync::Arc;
+
+use domain::testing::{InMemoryChannelRepository, NoopEventPublisher};
+use domain::value_objects::UserId;
+
+use crate::channels::commands::CreateChannelCommand;
+use crate::channels::deps::{ChannelCommandDeps, ChannelQueryDeps};
+use crate::channels::queries::GetChannelQuery;
+use crate::channels::{create, get};
+
+fn make_deps() -> (ChannelCommandDeps, ChannelQueryDeps) {
+    let repo = Arc::new(InMemoryChannelRepository::new());
+    let cmd_deps = ChannelCommandDeps {
+        channel_command: repo.clone(),
+        channel_query: repo.clone(),
+        event_publisher: Arc::new(NoopEventPublisher::new()),
+    };
+    let query_deps = ChannelQueryDeps {
+        channel_query: repo,
+    };
+    (cmd_deps, query_deps)
+}
+
+#[tokio::test]
+async fn get_existing_channel() {
+    let (cmd_deps, query_deps) = make_deps();
+
+    let channel = create::execute(
+        &cmd_deps,
+        CreateChannelCommand {
+            owner_id: UserId::generate().value(),
+            name: "Findable".into(),
+            timezone: "UTC".into(),
+        },
+    )
+    .await
+    .unwrap();
+
+    let found = get::execute(
+        &query_deps,
+        GetChannelQuery {
+            channel_id: channel.id().value(),
+        },
+    )
+    .await
+    .unwrap();
+
+    assert!(found.is_some());
+    assert_eq!(found.unwrap().name(), "Findable");
+}
+
+#[tokio::test]
+async fn get_nonexistent_returns_none() {
+    let (_, query_deps) = make_deps();
+
+    let found = get::execute(
+        &query_deps,
+        GetChannelQuery {
+            channel_id: uuid::Uuid::new_v4(),
+        },
+    )
+    .await
+    .unwrap();
+
+    assert!(found.is_none());
+}