upload files in separate thread, delete after upload

[dtracers]

We currently write file data and upload in the same thread as the one the bot logic is running in.

I think we can write the file data in the same thread but uploading the file data needs to happen in a separate thread.

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Files that upload successfully should be deleted from the local disk.

[Sciguymjm]

Due to GIL (global interpreter lock), there is a good chance the file upload will need to be a separate process/script.

[dtracers]

spawning a process to handle this should be fairly easy.
Maybe we make the server converter internally maintain its own process?