fix: Backup feature Chunk load error

[sub-hub]

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  • Have you tested your changes?
  • Have you checked that it won't break any existing features?
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  • Have you checked if it works normally in all models?
  • Have you checked if it works normally in all web, local, and node-hosted versions? If it doesn't, have you blocked it in those versions?
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  • Have you understood what the code does?
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Summary

Currently, An error occurs when trying to perform a backup after restart the web risu server.
The dynamic import streamsaver package does not work until reload the page because the address changes.

So I changed streamsaver import in LocalWriter to a static import for reliability (prevents backup failures if server restarts).
And added a global handler in main.ts for Vite’s vite:preloadError event. If a dynamic import fails (e.g., after server update), users are alerted that they needs to refresh the page.
There are other dynamic imports remaining, but I'm leaving them as is since they aren't important enough to convert to static.

Footnotes

1. Modifies the behavior of prompting, requesting, or handling responses from AI models. ↩

2. Over 80% of the code is AI generated. ↩

[cubicj]

Verified the backup export path and preload-error handling. Making streamsaver a static import removes the late chunk load from LocalWriter, and the global preload handler gives users a clear refresh path for remaining stale chunks.

Check, tests, and build pass locally.

Approving — thanks for the contribution!