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/application/src/import/deps.rs

@@ -50,11 +50,6 @@ pub struct ListImportProfilesDeps {
     pub import_profile: Arc<dyn ImportProfileRepository>,
 }
 
-/// Backs `apply_profile_and_map`, which internally drives `apply_profile::execute`
-/// then `apply_mapping::execute` — these fields are exactly the union of
-/// `ApplyProfileDeps` and `ApplyMappingDeps`'s fields, cloned once here and used to
-/// build each nested deps struct inline at the call site (see that file's doc
-/// comment for why: no use-case signature changes, per this task's constraints).
 pub struct ApplyProfileAndMapDeps {
     pub import_profile: Arc<dyn ImportProfileRepository>,
     pub import_session: Arc<dyn ImportSessionRepository>,