fix(sync): preserve queue if sendRemainingSteps fails

During a network disconnect
Yjs-websocket notices missing awareness messages and closes the connection.
In this case the remaining steps can also not be send out and the request fails.
Preserve the queue so we can use it once the network is back up.

Signed-off-by: Max <max@nextcloud.com>

src/services/WebSocketPolyfill.js

@@ -125,7 +125,9 @@ export default function initWebSocketPolyfill(syncService, fileId, initialSessio
 
 		#sendRemainingSteps() {
 			if (this.#queue.length) {
+				let outbox = []
 				return syncService.sendStepsNow(() => {
+					outbox = [...this.#queue]
 					const data = {
 						steps: this.#steps,
 						awareness: this.#awareness,
@@ -136,6 +138,7 @@ export default function initWebSocketPolyfill(syncService, fileId, initialSessio
 					return data
 				})?.catch(err => {
 					logger.error(err)
+					this.#queue = [...outbox, ...this.#queue]
 				})
 			}
 		}