feat: use misskey default maxFileSize for nginx config

[jojobii-arks]

resolves #22

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Summary

• When creating the Nginx config, the client_max_body_size is 80MB. However, Misskey defaults to a 250MB upload limit. Perhaps it's worth changing the config generation to match the Misskey defaults.

https://github.com/joinmisskey/bash-install/blob/692a60449e52d3f20de567af41bb78307bffb4cf/ubuntu.sh#L690

• See misskey/.config/example.yml. and the misskey/../DownloadService.ts using default values.

[tamaina]

👍

[tamaina]

But Cloudflare's Free plan only supports up to 100MB, so to upload large files, Misskey will need to support split uploads...