feat: Upgrade Global Presence to SSE architecture

- matrix-presence-aggregator v2 with SSE endpoint
- Created @presence_daemon Matrix user
- SSE proxy in Next.js /api/presence/stream
- Updated frontend to use SSE instead of WebSocket
- Real-time city online count and room presence

apps/web/src/app/api/presence/stream/route.ts

@@ -0,0 +1,64 @@
+import { NextRequest } from "next/server";
+
+export const runtime = "nodejs";
+export const dynamic = "force-dynamic";
+
+const PRESENCE_AGGREGATOR_URL = process.env.PRESENCE_AGGREGATOR_URL || "http://localhost:8085/presence/stream";
+
+export async function GET(req: NextRequest) {
+  try {
+    const upstream = await fetch(PRESENCE_AGGREGATOR_URL, {
+      headers: {
+        accept: "text/event-stream",
+      },
+    });
+
+    if (!upstream.ok) {
+      return new Response(
+        JSON.stringify({ error: "Failed to connect to presence aggregator" }),
+        { status: 502, headers: { "Content-Type": "application/json" } }
+      );
+    }
+
+    const readable = new ReadableStream({
+      start(controller) {
+        const reader = upstream.body!.getReader();
+
+        function push() {
+          reader.read().then(({ done, value }) => {
+            if (done) {
+              controller.close();
+              return;
+            }
+            controller.enqueue(value);
+            push();
+          }).catch((err) => {
+            console.error("SSE proxy error:", err);
+            controller.close();
+          });
+        }
+
+        push();
+      },
+      cancel() {
+        upstream.body?.cancel();
+      },
+    });
+
+    return new Response(readable, {
+      headers: {
+        "Content-Type": "text/event-stream",
+        "Cache-Control": "no-cache",
+        "Connection": "keep-alive",
+        "X-Accel-Buffering": "no",
+      },
+    });
+  } catch (error) {
+    console.error("SSE proxy connection error:", error);
+    return new Response(
+      JSON.stringify({ error: "Presence aggregator unavailable" }),
+      { status: 503, headers: { "Content-Type": "application/json" } }
+    );
+  }
+}
+

apps/web/src/app/city/page.tsx

@@ -10,7 +10,7 @@ import { useGlobalPresence } from '@/hooks/useGlobalPresence'
 export default function CityPage() {
   const [rooms, setRooms] = useState<CityRoom[]>([])
   const [loading, setLoading] = useState(true)
-  const presence = useGlobalPresence()
+  const { cityOnline, roomsPresence } = useGlobalPresence()
 
   useEffect(() => {
     async function fetchRooms() {
@@ -26,11 +26,12 @@ export default function CityPage() {
     fetchRooms()
   }, [])
 
-  // Calculate total online from presence or fallback to API data
-  const totalOnline = Object.values(presence).reduce((sum, p) => sum + p.online_count, 0) ||
-    rooms.reduce((sum, r) => sum + r.members_online, 0)
+  // Use SSE presence data if available, otherwise fallback to API data
+  const totalOnline = cityOnline > 0 
+    ? cityOnline 
+    : rooms.reduce((sum, r) => sum + r.members_online, 0)
   
-  const activeRooms = Object.values(presence).filter(p => p.online_count > 0).length ||
+  const activeRooms = Object.values(roomsPresence).filter(p => p.online > 0).length ||
     rooms.filter(r => r.members_online > 0).length
 
   if (loading) {
@@ -84,7 +85,7 @@ export default function CityPage() {
               <RoomCard 
                 key={room.id} 
                 room={room} 
-                livePresence={presence[room.slug]}
+                livePresence={roomsPresence[room.id]}
               />
             ))}
           </div>
@@ -124,13 +125,13 @@ export default function CityPage() {
 
 interface RoomCardProps {
   room: CityRoom
-  livePresence?: { online_count: number; typing_count: number }
+  livePresence?: { online: number; typing: number }
 }
 
 function RoomCard({ room, livePresence }: RoomCardProps) {
   // Use live presence if available, otherwise fallback to API data
-  const onlineCount = livePresence?.online_count ?? room.members_online
-  const typingCount = livePresence?.typing_count ?? 0
+  const onlineCount = livePresence?.online ?? room.members_online
+  const typingCount = livePresence?.typing ?? 0
   const isActive = onlineCount > 0
 
   return (