Fix compilation error caused by wrong WebSocket message type for SDP

This fixes an error introduced in https://review.jami.net/c/jami-web/+/23075.

Changes:
- Replace WebSocketRTCOffer and WebSocketRTCAnswer imports with WebRTCSDP
- Group all WebSocket interfaces in one file

Change-Id: Ie49aabc34647a5bb9cd983e6ae4e1b691cee6040
diff --git a/common/src/interfaces/websocket-interfaces.ts b/common/src/interfaces/websocket-interfaces.ts
new file mode 100644
index 0000000..cfbefb2
--- /dev/null
+++ b/common/src/interfaces/websocket-interfaces.ts
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2022 Savoir-faire Linux Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation; either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+import { Message } from '../Conversation.js';
+
+export interface ConversationMessage {
+  conversationId: string;
+  message: Message;
+}
+
+export interface ConversationView {
+  accountId: string;
+  conversationId: string;
+}
+
+export interface WebRTCSDP {
+  sdp: RTCSessionDescriptionInit;
+}
+
+export interface WebRTCIceCandidate {
+  candidate: RTCIceCandidate;
+}