feat(web): open spaces as a plain chat on phones with a side drawer

Spaces, channels, files, members and the account move into a left drawer,
the top bar keeps only the essentials, and touch devices get a tap menu
instead of always-visible delete buttons. Also fixes the history checkboxes
in the channel settings sheet.

web/src/features/channel/ThreadSidebar.tsx

@@ -91,8 +91,8 @@ export function ThreadSidebar(props: Props) {
           <option value="">未分组</option>{props.groups.map((group) => <option key={group.id} value={group.id}>{group.name}</option>)}
         </select></label> : null}
         {edit.kind === 'channel' && edit.id && props.owner ? <>
-          <label><input type="checkbox" checked={chatHistory} onChange={event => setChatHistory(event.target.checked)} />新成员可读历史聊天</label>
-          <label><input type="checkbox" checked={filesHistory} onChange={event => setFilesHistory(event.target.checked)} />新成员可读历史文件</label>
+          <label className={styles.check}><input type="checkbox" checked={chatHistory} onChange={event => setChatHistory(event.target.checked)} />新成员可读历史聊天</label>
+          <label className={styles.check}><input type="checkbox" checked={filesHistory} onChange={event => setFilesHistory(event.target.checked)} />新成员可读历史文件</label>
         </> : null}
         {error ? <p className={styles.error} role="alert">{error}</p> : null}
         <div className={`${styles.groupActions} ${styles.modalActions}`}>