feat: events date filter and preserve list page in URL (SAC 0.7.1)

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

frontend/src/views/EventDetailView.vue

@@ -4,7 +4,7 @@
 
     <RouterLink v-if="fromReports" :to="{ path: '/reports', query: backToReportsQuery }">← Отчёты</RouterLink>
 
-    <RouterLink v-else to="/events">← События</RouterLink>
+    <RouterLink v-else :to="{ path: '/events', query: backToEventsQuery }">← События</RouterLink>
 
   </p>
 
@@ -105,6 +105,7 @@ import { apiFetch, type EventDetail } from "../api";
 
 import ReportBodyCard from "../components/ReportBodyCard.vue";
 
+import { eventsBackQueryFromDetail } from "../utils/eventsListQuery";
 import { isDailyReportType } from "../utils/reportDisplay";
 
 
@@ -134,6 +135,8 @@ const backToReportsQuery = computed(() => {
   return q;
 });
 
+const backToEventsQuery = computed(() => eventsBackQueryFromDetail(route.query));
+
 
 
 function formatDt(iso: string) {