Add real-time WebSocket task progress with multi-job drawer

Replace 5s HTTP polling with WebSocket-based real-time updates for task
progress. Celery workers publish progress to Redis pub/sub channels;
a FastAPI WebSocket endpoint subscribes and forwards to the browser.
Polling is kept as a 30s fallback when WebSocket is unavailable.

The task progress drawer now supports multiple concurrent jobs with a
tab bar for switching between scrape and POI distance tasks.

Backend:
- Add services/task_progress_publisher.py (Redis pub/sub bridge)
- Add api/ws_routes.py (WebSocket endpoint with JWT auth)
- Publish progress from listing_tasks and poi_tasks
- Publish REVOKED via pub/sub on cancel/clear to fix stuck UI

Frontend:
- Add useTaskWebSocket hook with reconnection and keepalive
- Add TaskState and WS message types
- TaskIndicator: WS-driven updates with polling fallback
- TaskProgressDrawer: multi-job tabs, POI phase timeline
- Guard against WS overwriting local cancel state

frontend/src/components/Header.tsx

@@ -1,4 +1,5 @@
 import type { AuthUser } from '@/auth/types';
+import type { TaskState } from '@/types';
 import { Button } from './ui/button';
 import { Separator } from './ui/separator';
 import { LogOut, Home, Filter } from 'lucide-react';
@@ -16,6 +17,9 @@ interface HeaderProps {
     showFilterToggle?: boolean;
     onTaskCancelled?: () => void;
     onTaskCompleted?: () => void;
+    wsTasks?: Record<string, TaskState>;
+    wsConnected?: boolean;
+    wsSubscribe?: (taskId: string) => void;
 }
 
 export function Header({
@@ -26,6 +30,9 @@ export function Header({
     showFilterToggle = false,
     onTaskCancelled,
     onTaskCompleted,
+    wsTasks,
+    wsConnected,
+    wsSubscribe,
 }: HeaderProps) {
     const handleLogout = async () => {
         if (user.provider === 'passkey') {
@@ -50,7 +57,13 @@ export function Header({
             <HealthIndicator />
 
             {/* Task Indicator */}
-            <TaskIndicator taskID={taskID ?? null} onTaskCancelled={onTaskCancelled} onTaskCompleted={onTaskCompleted} />
+            <TaskIndicator
+                taskID={taskID ?? null}
+                onTaskCancelled={onTaskCancelled}
+                onTaskCompleted={onTaskCompleted}
+                wsTasks={wsTasks}
+                wsConnected={wsConnected}
+            />
 
             {/* Filter Toggle (mobile) */}
             {showFilterToggle && (