Remove matrix-events-sdk dependency (#31398)

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/components/structures/ThreadPanel.tsx

@@ -6,7 +6,6 @@ SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Com
 Please see LICENSE files in the repository root for full details.
 */
 
-import { type Optional } from "matrix-events-sdk";
 import React, { useContext, useEffect, useRef, useState } from "react";
 import { type EventTimelineSet, type Room, Thread } from "matrix-js-sdk/src/matrix";
 import { IconButton, Tooltip } from "@vector-im/compound-web";
@@ -163,7 +162,7 @@ const ThreadPanel: React.FC<IProps> = ({ roomId, onClose, permalinkCreator }) =>
     const [room, setRoom] = useState<Room | null>(null);
     const [narrow, setNarrow] = useState<boolean>(false);
 
-    const timelineSet: Optional<EventTimelineSet> =
+    const timelineSet: EventTimelineSet | undefined =
         filterOption === ThreadFilterType.My ? room?.threadsTimelineSets[1] : room?.threadsTimelineSets[0];
     const hasThreads = Boolean(room?.threadsTimelineSets?.[0]?.getLiveTimeline()?.getEvents()?.length);