perf(web): shorten the first open of a space for new members

Accepting an invitation no longer waits for the vault sync, the redundant
join right after joining is skipped, and the crypto state, first log page and
channel metadata are requested in parallel.

web/src/core-bridge/worker/channelEvents.ts

@@ -129,15 +129,19 @@ export async function channelMetadata(resource: SavedResource, session: ChannelS
 }
 
 export async function syncChannel(resource: SavedResource, session: ChannelSession, signal: AbortSignal): Promise<number> {
-  if (resource.mode === 'enc') await readDataKeys(resource, session);
+  // reset 必须同步发出:connectChannel 随后并行拉取频道信息,它们的结果要落在 reset 之后
   publishWorkspace(resource.id, { t: 'reset' });
   clearFileCatalog(resource.id);
   readers.set(resource.id, session.createItemReader());
+  // 密钥与第一页日志互不依赖,同时发出,首次打开少等一个往返
+  const keys = resource.mode === 'enc' ? readDataKeys(resource, session) : undefined;
+  keys?.catch(() => undefined);
   let from = 0;
-  for (;;) {
+  for (let first = true; ; first = false) {
     const response = await apiFetch(`/channels/${resource.id}/log?from=${from}&limit=200`, {
       headers: session.authHeaders('read'), signal,
     });
+    if (first) await keys;
     const records = parseLogRecords(new Uint8Array(await response.arrayBuffer()));
     for (const record of records) {
       await applyChannelRecord(resource, session, record);