writeAtomic, everywhere a file lands

the .part-then-rename rule was applied at two upload routes yesterday and
by this morning the platform had a dozen other writes putting files in the
same folders — an OCR result beside its image, a TTS clip, a download
landing, a save from the editor — every one straight to the final name. a
guarantee that holds for two of fourteen paths is not a guarantee, and the
next person adding a fifteenth had nothing to copy.

so it is a function now, and every durable write goes through it: the file
browser, sendoff, task definitions, skill and tool files, bug reports,
scraped attachments, the chat provider config.

the failure it prevents is silent rather than loud. a truncated m4a decodes
fine, it is simply short — a commander transcribing recordings as they land
would produce a clean transcript of the first few seconds of a two-minute
memo and report success.

two things learned writing it. Bun.write creates the parent chain itself,
so the mkdir option i added was dead weight and several callers were doing
it twice. and Parameters<typeof Bun.write>[1] resolves to the first
overload only — BunFile — which rejects the string and Buffer every caller
actually passes.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Officer-Session: 656f5c85-e49a-4f1f-b9f3-042a04b4d043

src/servers/api/scrape/scrape.ts

@@ -3,6 +3,7 @@ import { mkdir } from 'node:fs/promises';
 import { join } from 'node:path';
 import { chromium, type Browser } from 'playwright';
 import { getTmpAttachmentsDir, getAttachmentsDir } from '@@/data-path';
+import { writeAtomic } from '@@/write-atomic';
 
 const MAX_CONTENT_LENGTH = 100_000;
 
@@ -148,7 +149,7 @@ scrapeRouter.post('/', async (ctx) => {
     }
 
     await mkdir(saveDir, { recursive: true });
-    await Bun.write(join(saveDir, attachmentId), html);
+    await writeAtomic(join(saveDir, attachmentId), html);
 
     return ctx.json({ url, title, content, attachmentId });
   } catch (err) {