refactor: split monolithic handlers + testing into domain-grouped modules

handlers/api.rs (1706 LOC) + html.rs (1735 LOC) → 12 domain files:
auth, diary, movies, users, search, watchlist, goals, social,
integrations, helpers + existing import/webhook/wrapup/images/rss.

domain/testing.rs (1309 LOC) → testing/ module:
in_memory, fakes, noops, panics, wrapup.

Update README + architecture.mmd with goals feature.

crates/domain/src/testing/noops.rs

@@ -0,0 +1,191 @@
+use std::sync::{Arc, Mutex};
+
+use async_trait::async_trait;
+
+use crate::{
+    errors::DomainError,
+    events::DomainEvent,
+    ports::{EventPublisher, ObjectStorage},
+    value_objects::UserId,
+};
+
+// ── NoopEventPublisher ────────────────────────────────────────────────────────
+
+pub struct NoopEventPublisher {
+    pub events: Mutex<Vec<DomainEvent>>,
+}
+
+impl NoopEventPublisher {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            events: Mutex::new(vec![]),
+        })
+    }
+
+    pub fn published(&self) -> Vec<DomainEvent> {
+        self.events.lock().unwrap().clone()
+    }
+}
+
+#[async_trait]
+impl EventPublisher for NoopEventPublisher {
+    async fn publish(&self, event: &DomainEvent) -> Result<(), DomainError> {
+        self.events.lock().unwrap().push(event.clone());
+        Ok(())
+    }
+}
+
+// ── NoopObjectStorage ──────────────────────────────────────────────────────────
+
+pub struct NoopObjectStorage;
+
+#[async_trait]
+impl ObjectStorage for NoopObjectStorage {
+    async fn store(&self, key: &str, _image_bytes: &[u8]) -> Result<String, DomainError> {
+        Ok(format!("noop://{key}"))
+    }
+
+    async fn get(&self, _key: &str) -> Result<Vec<u8>, DomainError> {
+        Ok(vec![])
+    }
+
+    async fn get_stream(
+        &self,
+        _key: &str,
+    ) -> Result<futures::stream::BoxStream<'static, Result<bytes::Bytes, DomainError>>, DomainError>
+    {
+        Ok(Box::pin(futures::stream::empty()))
+    }
+
+    async fn delete(&self, _key: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
+}
+
+// ── NoopRemoteWatchlistRepository ─────────────────────────────────────────────
+
+pub struct NoopRemoteWatchlistRepository;
+
+#[async_trait]
+impl crate::ports::RemoteWatchlistRepository for NoopRemoteWatchlistRepository {
+    async fn save(&self, _: crate::models::RemoteWatchlistEntry) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn remove_by_ap_id(&self, _: &str, _: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn get_by_actor_url(
+        &self,
+        _: &str,
+    ) -> Result<Vec<crate::models::RemoteWatchlistEntry>, DomainError> {
+        Ok(vec![])
+    }
+    async fn remove_all_by_actor(&self, _: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn get_by_derived_uuid(
+        &self,
+        _: uuid::Uuid,
+    ) -> Result<Vec<crate::models::RemoteWatchlistEntry>, DomainError> {
+        Ok(vec![])
+    }
+}
+
+// ── NoopSocialQueryPort ───────────────────────────────────────────────────────
+
+pub struct NoopSocialQueryPort;
+
+#[async_trait]
+impl crate::ports::SocialQueryPort for NoopSocialQueryPort {
+    async fn get_accepted_following_urls(&self, _: uuid::Uuid) -> Result<Vec<String>, DomainError> {
+        Ok(vec![])
+    }
+    async fn list_all_followed_remote_actors(
+        &self,
+    ) -> Result<Vec<crate::ports::RemoteActorInfo>, DomainError> {
+        Ok(vec![])
+    }
+    async fn count_following(&self, _: uuid::Uuid) -> Result<usize, DomainError> {
+        Ok(0)
+    }
+    async fn count_accepted_followers(&self, _: uuid::Uuid) -> Result<usize, DomainError> {
+        Ok(0)
+    }
+    async fn get_pending_followers(
+        &self,
+        _: uuid::Uuid,
+    ) -> Result<Vec<crate::ports::PendingFollowerInfo>, DomainError> {
+        Ok(vec![])
+    }
+}
+
+// ── NoopGoalRepository ────────────────────────────────────────────────────────
+
+pub struct NoopGoalRepository;
+
+#[async_trait]
+impl crate::ports::GoalRepository for NoopGoalRepository {
+    async fn save(&self, _: &crate::models::Goal) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn update(&self, _: &crate::models::Goal) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn delete(
+        &self,
+        _: &crate::value_objects::GoalId,
+        _: &UserId,
+    ) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn find_by_user_and_year(
+        &self,
+        _: &UserId,
+        _: u16,
+    ) -> Result<Option<crate::models::Goal>, DomainError> {
+        Ok(None)
+    }
+    async fn list_for_user(&self, _: &UserId) -> Result<Vec<crate::models::Goal>, DomainError> {
+        Ok(vec![])
+    }
+    async fn count_reviews_in_year(&self, _: &UserId, _: u16) -> Result<u32, DomainError> {
+        Ok(0)
+    }
+}
+
+// ── NoopUserSettingsRepository ────────────────────────────────────────────────
+
+pub struct NoopUserSettingsRepository;
+
+#[async_trait]
+impl crate::ports::UserSettingsRepository for NoopUserSettingsRepository {
+    async fn get(&self, user_id: &UserId) -> Result<crate::models::UserSettings, DomainError> {
+        Ok(crate::models::UserSettings::new(user_id.clone()))
+    }
+    async fn save(&self, _: &crate::models::UserSettings) -> Result<(), DomainError> {
+        Ok(())
+    }
+}
+
+// ── NoopRemoteGoalRepository ──────────────────────────────────────────────────
+
+pub struct NoopRemoteGoalRepository;
+
+#[async_trait]
+impl crate::ports::RemoteGoalRepository for NoopRemoteGoalRepository {
+    async fn save(&self, _: crate::models::RemoteGoalEntry) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn update_by_ap_id(&self, _: &str, _: u32, _: u32) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn remove_by_ap_id(&self, _: &str, _: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
+    async fn get_by_actor_url(
+        &self,
+        _: &str,
+    ) -> Result<Vec<crate::models::RemoteGoalEntry>, DomainError> {
+        Ok(vec![])
+    }
+}