feat: always-on Insights — correlation analysis over viewing habits

Conservative, live insights (ADR-0010) derived from each user's diary:
rating lift by genre (first-time watches only), genre seasonality vs a
uniform 1/12 month baseline, medium weekend-lift, and watch-time rhythm.

- domain: WatchRow model, InsightsQuery port, pure insights_analyzer with
  all honesty thresholds (sample minimums, strength cutoffs, suppressions
  for import noise), unit-tested
- adapters: thin Sqlite/Postgres fetch twins, reusing WrapUp's genre fetch
- application: get_insights use case, InsightsGroup in Deps
- composition/server: wiring through Repositories/DatabaseOutput
- presentation: GET /api/v1/insights handler, typed serde-tagged DTOs,
  openapi doc
- spa: /insights route (shadcn cards), insights feature hook, profile
  entry link, en locale strings
- server test: end-to-end seed sqlite → HTTP → rating lift + rhythm

Also records ADR-0010, defines "Insight" in the glossary, and includes
pre-existing worktree comment-stripping cleanups.

crates/adapters/postgres-social/src/lib.rs

@@ -11,14 +11,6 @@ pub use remote_goals::PostgresRemoteGoalRepository;
 
 use sqlx::PgPool;
 
-/// Postgres-backed implementations of the *domain* social ports.
-///
-/// Deliberately separate from `postgres-federation`: this crate knows nothing
-/// about ActivityPub, which is what allows a build with the `federation`
-/// feature off to exclude the federation stack entirely. See ADR-0009.
-///
-/// Shares the `ap_followers` / `ap_following` tables with
-/// `postgres-federation`; neither crate owns migrations.
 pub struct PostgresSocialRepository {
     pub(crate) pool: PgPool,
     pub(crate) instance: domain::value_objects::InstanceIdentity,