Incoming call in DM shows only "Join" button, no notification toast, no ringing sound, no call history chat in timeline

### Steps to reproduce

1. Create a DM room between two users

2. Configure Element Web to use Element Call with LiveKit as the transport

3. User A initiates a call from Element X Android to User B who is using Element Web

4. User B sees only a "Join" button — there is no incoming call toast with "Accept"/"Decline" buttons, no ringing sound when the call arrives, and no call information appears in the chat timeline

5. After clicking "Join", the call connects successfully
6. the chat timeline shows no message about who called or that a call was missed

### Outcome

What Works
Element Call widget loads correctly

JWT tokens are generated properly by lk-jwt service

LiveKit connection establishes successfully

Audio/video works after clicking "Join"

Group calls (3+ participants) work correctly

What Does NOT Work in DM Rooms
No toast notification with "Accept"/"Decline" buttons

No ringing sound on incoming call

No message in timeline about incoming call chat

No missed call chat message when unanswered

Only a "Join" button appears

### Operating system

ubuntu 22.04, WIndows 11

### Browser information

Chrome, Microsoft Edge, Opera GX

### URL for webapp

_No response_

### Application version

Caller: Element X Android 26.03.3

Receiver: Element Web 1.12.13

Widget ElementCall

Transport: LiveKit 1.9.12

lk-jwt-service: 0.4.1

Synapse: 1.150.0

Matrix Authentication Service (MAS): mas-cli v1.14.0

### Homeserver

Synapse version: 1.150.0

### Will you send logs?

Yes