feat(vpn): монитор актуальности Яндекс Телемост + инструкция про выход из встречи

- INSTRUCTIONS_TEXT: добавлено требование выйти из встречи, а не завершать её
- vpn.db.ts: findAllActiveVpnTasks для поиска активных VPN-задач
- vpn.service.ts: checkVpnRoomsValidity — периодическая проверка комнат, concurrency=5
- vpn-bot.service.ts: findVpnBotConversationId и notifyVpnRoomExpired
- server/index.ts: worker каждые 6 часов, уведомление пользователю о протухшей ссылке

server/vpn/vpn.db.ts

@@ -290,3 +290,79 @@ export async function updateVpnTaskFieldMap(
     await setVpnTaskField(taskId, code, value, organizationId);
   }
 }
+
+export interface ActiveVpnTaskInfo {
+  taskId: number;
+  organizationId: number;
+  createdBy: number;
+  roomUrl: string;
+}
+
+export async function findAllActiveVpnTasks(): Promise<ActiveVpnTaskInfo[]> {
+  // Find all organizations that have VPN tasks
+  const orgRows = await db
+    .select({ orgId: tasks.organizationId })
+    .from(tasks)
+    .where(eq(tasks.formId, VPN_FORM_ID))
+    .groupBy(tasks.organizationId);
+
+  const results: ActiveVpnTaskInfo[] = [];
+
+  for (const { orgId } of orgRows) {
+    try {
+      const cache = await getVpnFormCache(orgId);
+      const statusFieldId = getFieldId(cache, 'status');
+      const activeFieldId = getFieldId(cache, 'is_active');
+      const roomUrlFieldId = getFieldId(cache, 'room_url');
+
+      const rows = await db
+        .select({
+          taskId: tasks.id,
+          createdBy: tasks.createdBy,
+          roomUrl: taskFieldValues.value,
+        })
+        .from(tasks)
+        .innerJoin(
+          taskFieldValues,
+          and(
+            eq(taskFieldValues.taskId, tasks.id),
+            eq(taskFieldValues.formId, VPN_FORM_ID),
+            eq(taskFieldValues.fieldId, roomUrlFieldId),
+          ),
+        )
+        .where(
+          and(
+            eq(tasks.formId, VPN_FORM_ID),
+            eq(tasks.organizationId, orgId),
+            sql`exists (
+              select 1 from task_field_values tfv
+              where tfv.task_id = tasks.id
+                and tfv.field_id = ${statusFieldId}
+                and tfv.value = to_jsonb('Активна'::text)
+            )`,
+            sql`exists (
+              select 1 from task_field_values tfv
+              where tfv.task_id = tasks.id
+                and tfv.field_id = ${activeFieldId}
+                and tfv.value = to_jsonb(true)
+            )`,
+          ),
+        );
+
+      for (const row of rows) {
+        if (typeof row.roomUrl === 'string' && row.roomUrl) {
+          results.push({
+            taskId: row.taskId,
+            organizationId: orgId,
+            createdBy: row.createdBy,
+            roomUrl: row.roomUrl,
+          });
+        }
+      }
+    } catch (err) {
+      console.error(`[VPN DB] findAllActiveVpnTasks error for org ${orgId}:`, err);
+    }
+  }
+
+  return results;
+}