add 400+ unit tests for domain and application layers

Extract ReviewLogger trait to decouple import/integrations
from diary::log_review (cross-module coupling smell).

Add in-memory fakes for all repository ports, enabling
isolated testing of every use case module without a database.

Coverage: domain+application 22% → 80%, 427 tests.

crates/application/src/integrations/tests/confirm.rs

@@ -0,0 +1,372 @@
+use std::sync::Arc;
+
+use domain::models::{WatchEvent, WatchEventSource};
+use domain::ports::{MovieRepository, WatchEventRepository};
+use domain::testing::{InMemoryWatchEventRepository, NoopEventPublisher};
+use domain::value_objects::UserId;
+use uuid::Uuid;
+
+use crate::integrations::commands::{ConfirmWatchEventsCommand, WatchEventConfirmation};
+use crate::integrations::confirm;
+use crate::test_helpers::TestContextBuilder;
+
+#[tokio::test]
+async fn confirms_watch_event_via_review_logger() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "Test Movie".into(),
+        Some(2024),
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .with_event_publisher(Arc::clone(&events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 4,
+                comment: None,
+            }],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 1);
+}
+
+#[tokio::test]
+async fn empty_confirmations_returns_zero() {
+    let ctx = TestContextBuilder::new().build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: Uuid::new_v4(),
+            confirmations: vec![],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 0);
+}
+
+#[tokio::test]
+async fn confirms_event_with_external_metadata_id_and_no_movie_id() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "External Movie".into(),
+        Some(2023),
+        Some("tt1234567".into()),
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .with_event_publisher(Arc::clone(&events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 3,
+                comment: Some("Great film".into()),
+            }],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 1);
+}
+
+#[tokio::test]
+async fn rejects_other_users_event() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let owner = Uuid::new_v4();
+    let intruder = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(owner),
+        "Movie".into(),
+        None,
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: intruder,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 3,
+                comment: None,
+            }],
+        },
+    )
+    .await;
+
+    assert!(result.is_err());
+}
+
+#[tokio::test]
+async fn fails_when_event_not_found() {
+    let ctx = TestContextBuilder::new().build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: Uuid::new_v4(),
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: Uuid::new_v4(),
+                rating: 4,
+                comment: None,
+            }],
+        },
+    )
+    .await;
+
+    assert!(result.is_err());
+}
+
+#[tokio::test]
+async fn confirms_event_with_movie_id() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+    let movie_uuid = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "Movie With Id".into(),
+        Some(2024),
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        Some(domain::value_objects::MovieId::from_uuid(movie_uuid)),
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    // Also seed movie repo so review_logger can find it
+    let movies = domain::testing::InMemoryMovieRepository::new();
+    let movie = domain::models::Movie::from_persistence(
+        domain::value_objects::MovieId::from_uuid(movie_uuid),
+        None,
+        domain::value_objects::MovieTitle::new("Movie With Id".into()).unwrap(),
+        domain::value_objects::ReleaseYear::new(2024).unwrap(),
+        None,
+        None,
+    );
+    movies.upsert_movie(&movie).await.unwrap();
+
+    // Build a real review logger
+    let reviews = domain::testing::InMemoryReviewRepository::new();
+    let watchlist = domain::testing::InMemoryWatchlistRepository::new();
+    let review_logger = std::sync::Arc::new(crate::diary::review_logger::DefaultReviewLogger::new(
+        std::sync::Arc::clone(&movies) as _,
+        std::sync::Arc::clone(&reviews) as _,
+        std::sync::Arc::clone(&watchlist) as _,
+        std::sync::Arc::new(domain::testing::FakeMetadataClient) as _,
+        std::sync::Arc::clone(&events) as _,
+    ));
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(std::sync::Arc::clone(&watch_events) as _)
+        .with_event_publisher(std::sync::Arc::clone(&events) as _)
+        .with_movies(std::sync::Arc::clone(&movies) as _)
+        .with_review_logger(review_logger as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 4,
+                comment: None,
+            }],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 1);
+}
+
+#[tokio::test]
+async fn confirms_event_without_movie_id_and_without_external_metadata_id() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "Title Only Movie".into(),
+        Some(2022),
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .with_event_publisher(Arc::clone(&events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 5,
+                comment: Some("Amazing".into()),
+            }],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 1);
+}
+
+#[tokio::test]
+async fn confirms_multiple_events() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+
+    let event1 = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "Movie One".into(),
+        Some(2020),
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let id1 = event1.id().value();
+
+    let event2 = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "Movie Two".into(),
+        Some(2021),
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let id2 = event2.id().value();
+
+    watch_events.save(&event1).await.unwrap();
+    watch_events.save(&event2).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .with_event_publisher(Arc::clone(&events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![
+                WatchEventConfirmation {
+                    watch_event_id: id1,
+                    rating: 3,
+                    comment: None,
+                },
+                WatchEventConfirmation {
+                    watch_event_id: id2,
+                    rating: 4,
+                    comment: None,
+                },
+            ],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 2);
+}
+
+#[tokio::test]
+async fn confirms_event_without_year() {
+    let watch_events = InMemoryWatchEventRepository::new();
+    let events = NoopEventPublisher::new();
+    let uid = Uuid::new_v4();
+
+    let event = WatchEvent::new(
+        UserId::from_uuid(uid),
+        "No Year Movie".into(),
+        None, // no year
+        None,
+        WatchEventSource::Jellyfin,
+        chrono::Utc::now().naive_utc(),
+        None,
+    );
+    let event_id = event.id().value();
+    watch_events.save(&event).await.unwrap();
+
+    let ctx = TestContextBuilder::new()
+        .with_watch_events(Arc::clone(&watch_events) as _)
+        .with_event_publisher(Arc::clone(&events) as _)
+        .build();
+
+    let result = confirm::execute(
+        &ctx,
+        ConfirmWatchEventsCommand {
+            user_id: uid,
+            confirmations: vec![WatchEventConfirmation {
+                watch_event_id: event_id,
+                rating: 3,
+                comment: None,
+            }],
+        },
+    )
+    .await
+    .unwrap();
+
+    assert_eq!(result, 1);
+}