feat: dashboard top hosts/types, problems 24h, drill-down (d2-2)

- Extend /dashboards/summary; Events filters from query (hostname, severity)

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/work-plan.md

@@ -88,7 +88,7 @@
 ### День 2
 
 - [x] `d2-1` UI Problems: список, фильтры, `Ack/Resolve`, карточка с таймлайном
-- [ ] `d2-2` Dashboard: top hosts/types, `open vs resolved 24h`, drill-down
+- [x] `d2-2` Dashboard: top hosts/types, `open vs resolved 24h`, drill-down
 - [ ] `d2-3` Ops: retention, health checks, runbook backup/restore/deploy
 - [ ] `dod` DoD: нет дублей `event_id`, Problems e2e, 3 правила, UI MVP, docs, push в kalinamall
 
@@ -118,8 +118,8 @@
 
 - [x] `09:00–11:00` UI Problems: таблица + фильтры (`status/severity/host`)
 - [x] `11:00–12:00` карточка проблемы + таймлайн событий
-- [ ] `13:00–14:30` Dashboard: виджеты top hosts/types
-- [ ] `14:30–16:00` Dashboard: `open/resolved 24h` + drill-down
+- [x] `13:00–14:30` Dashboard: виджеты top hosts/types
+- [x] `14:30–16:00` Dashboard: `open/resolved 24h` + drill-down
 - [ ] `16:00–17:00` retention job (`events 30–90d`, `problems 180d+`)
 - [ ] `17:00–18:00` health checks (DB/worker/heartbeat stale)
 - [ ] `18:00–19:00` runbook + финальный push в kalinamall + freeze dev