feat: per-entity federation privacy toggles for reviews and watchlist

- add federate_reviews + federate_watchlist to UserSettings (default true)
- new UserFederationSettingsQuery port with FederationFlags struct
- remove get_user_federate_goals from LocalApContentQuery
- gate ReviewLogged, ReviewUpdated, WatchlistEntryAdded, on_poster_synced on flags
- goals gating migrated to UserFederationSettingsQuery
- ReviewDeleted and WatchlistEntryRemoved ungated (tombstones always fire)
- sqlite + postgres migrations and adapter impls
- settings API and SPA toggles

crates/api-types/src/goals.rs

@@ -29,9 +29,13 @@ pub struct UpdateGoalRequest {
 #[derive(Debug, Clone, Serialize, Deserialize, utoipa::ToSchema)]
 pub struct UserSettingsDto {
     pub federate_goals: bool,
+    pub federate_reviews: bool,
+    pub federate_watchlist: bool,
 }
 
 #[derive(Debug, Clone, Deserialize, utoipa::ToSchema)]
 pub struct UpdateUserSettingsRequest {
     pub federate_goals: bool,
+    pub federate_reviews: bool,
+    pub federate_watchlist: bool,
 }