feat(web): inline previews in chat and per-upload download limit choice

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

@@ -87,7 +87,8 @@ async function runJob(job: Job): Promise<void> {
     const prepared = await prepareObject(resource, session, threadId, 'files');
     const plan = session.encryptFile(file, {}, {
       itemId: prepared.itemIdBytes,
-      ...(options.directPreview ? { gated: 'auto' as const } : { gated: true, maxDownloads: options.maxDownloads }),
+      // 小文件(一帧放得下)且不限制次数:不设上限,加入者直接预览。其余都带上每个文件的下载次数(0 = 不限)
+      ...(options.directPreview && file.size < maxFrameData - 1024 ? { gated: 'auto' as const } : { gated: true, maxDownloads: options.maxDownloads }),
       ts, maxFrameData, threadId, folderId,
     });
     item = {
@@ -95,9 +96,7 @@ async function runJob(job: Job): Promise<void> {
       ...(author ? { author } : {}),
       ...(threadId ? { threadId } : {}), ...(folderId ? { folderId } : {}), ...(localId ? { localId } : {}),
       name: file.name, mime: file.type || 'application/octet-stream', size: file.size,
-      remaining: plan.gated
-        ? (options.directPreview ? resource.maxDownloads ?? 0 : options.maxDownloads) || null
-        : null,
+      remaining: plan.gated ? options.maxDownloads || null : null,
       preview: previewKindOf(file.type, file.name), gated: plan.gated,
     };
     job.itemId = item.id;