feat: Add presence heartbeat for Matrix online status

- matrix-gateway: POST /internal/matrix/presence/online endpoint
- usePresenceHeartbeat hook with activity tracking
- Auto away after 5 min inactivity
- Offline on page close/visibility change
- Integrated in MatrixChatRoom component

.viteignore

@@ -0,0 +1,9 @@
+src/app.ts
+src/infra/**
+src/services/**
+src/domain/**
+src/api/http/**
+src/api/middleware/**
+
+
+