feat: remove background from invite embed and modal

[gabrielfordevelopment]

closes #977 if I did it correctly. The feature wasn't detailed well, so I had to figure out something. If need further investigation, please let me know

• Removed the background color from the Invite message embed to blend with the chat.

• Removed the server banner backdrop from the Invite modal for a cleaner appearance.

• Cleaned up unused background image references in the Authentication page.

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Before

After

[ThomasJRyan]

I appreciate the attempt given the lack of information. I've added @insertish and @infi to take a look. Hopefully I can add more details to those tickets soon

[Pecacheu]

I don't get the appeal personally, looks less clean to me, like the content is bleeding out because you can't tell where the box starts and ends, it's more visually confusing design.

[infi]

This PR is not eligible for merge as it contains many changes which should all be in separate PRs.
Besides this, those are also not changes that we want to explore at the moment.

[gabrielfordevelopment]

those are also not changes that we want to explore at the moment.

I do not understand what you mean by this, since insertish literally made a milestone for this specific feature request:

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[Pecacheu]

Hmm, I'm just guessing here cause the wording is vague, but perhaps they meant this invite background.

That does make more sense- Personally I like it because it gives each server's invite a fun and unique feel, but I can see how it's a bit... much for some people, especially depending on how flashy the banner image is. Perhaps making it dimmer and adding a shadow backdrop to the modal would help instead? But that's a discussion for elsewhere!

[amycatgirl]

But that's a discussion for elsewhere!

Agreed, discussions for what the issue is referring to should be made in #977.

Edit: i read the issue number wrong, fixed it