feat(embed): add the ability to pass disnake.File to more Embed methods

[Snipy7374]

Summary

• Closes Local embed icons #1184

Unfortunately seems like the client (at least the web client) have a bug when displaying more than 1 local file uploaded using attachment:// links (this is still unconfirmed). Let me know if this is not true in your local discord client.

For more info check this message

Checklist

• If code changes were made, then they have been tested
  • I have updated the documentation to reflect the changes
  • I have formatted the code properly by running pdm lint
  • I have type-checked the code by running pdm pyright
• This PR fixes an issue
• This PR adds something new (e.g. new method or parameters)
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, ...)

[Snipy7374]

Apparently the issue is that the files have all the same filename, we should at least mention this in the docs

[Enegg]

I've left some minor docs change suggestions.

Would be nice if we could unify all the parameters under some common Asset object (iirc something hikari does?), but it might be a late call for that
Not very object oriented design smh

[Enegg]

lgtm 👍

[shiftinv]

lgtm, thank you!